American Top 40

1970–88: First Casey Kasem era

American Top 40 began on the Independence Day weekend in 1970, on seven radio stations, the very first being KDEO in El Cajon, California (now KECR), which broadcast the inaugural show the evening of July 3, 1970. The chart data broadcast actually included the top 40 songs from the week ending July 11, 1970. The very first show featured the very last time both Elvis Presley and The Beatles had songs simultaneously in the Top 10. It was originally distributed by Watermark Inc., and was first presented in mono until it started recording in stereo in September 1972. In early 1982, Watermark was purchased by ABC Radio and AT40 became a program of the "ABC Contemporary Radio Network". The program was hosted by Casey Kasem and co-created by Kasem; Don Bustany, Kasem's childhood friend from Detroit, MI; radio veteran Tom Rounds; and 93/KHJ Program Director Ron Jacobs, who produced and directed the various production elements. Rounds was also the marketing director; the initial funder was California strawberry grower Tom Driscoll.

The show began as a three-hour program written and directed by Bustany, counting down the top 40 songs on Billboard's Hot 100 Singles chart. The show quickly gained popularity once it was commissioned, and expanded to a four-hour-program on October 7, 1978, to reflect the increasing average length of singles on Billboard's Hot 100 chart. The producing staff expanded to eight people, some of them still in the business: Nikki Wine, Ben Marichal, Scott Paton, Matt Wilson, Merrill Shindler, Guy Aoki, Ronnie Allen and Sandy Stert Benjamin. (Bustany retired from AT40 in 1989; since 1994, he has hosted a political talk show on listener-sponsored KPFK.) By the early 1980s, the show could be heard on 520 stations in the United States and at its zenith, the show was broadcast on 1,000-plus stations in some 50 countries. Kasem told the New York Times in 1990 "I accentuate the positive and eliminate the negative. That is the timeless thing."

Features of the Kasem-era shows

During Kasem's run as host, the AT40 show had a number of popular and distinguishing features, some of which Kasem had done for some time at stations like KRLA in Los Angeles:

The top-ranking song on the chart always was introduced with one of these stories, which would be followed with a drum roll and the final reveal. Here is an example from the week of October 8, 1983:

Although the show's format implied an average of ten countdown songs per hour (once the show had gone to a four-hour format), this was not rigidly enforced; however, by the mid-1980s, it had become increasingly rare for the final hour of the show to have any more than the top eleven or any fewer than the top nine songs left to play. The songs' run times determined how many would comfortably fit into each hour. The show bent to fit the Billboard rankings, and some songs had to be edited (in addition to whatever edits had been done for the single release), with a verse or chorus cut (usually for songs on their way out of the countdown), in order to fit into the show. But Kasem and his producers never lost sight of the stations carrying their show, and that the stories behind the songs were the chief reason that listeners tuned to AT40.

1988–95: Shadoe Stevens era

In 1988, Kasem left the show over contract concerns with ABC. Industry trade paper Billboard magazine reported that the main disputes between Kasem and Watermark/ABC were over his salary, because of declining ratings and a smaller group of stations airing the show. Casey's final AT40 show, the 940th in the series, aired on August 6, 1988. At no point during that final show did Kasem ever let on that any changes were afoot. However, he closed the show by telling the audience to catch him on the television show America's Top 10 and did not plug the following week's AT40 (since December 19, 1987, he had always plugged both during his signoff).

Kasem was replaced by Shadoe Stevens, whose first American Top 40 show aired on August 13, 1988, on 1,014 stations. To introduce Stevens to the audience, a two-minute cold open was recorded to start the show with Stevens making his way to the studio through the show's fictitious hall of history; Kasem was mentioned during the course of the open, as a "giant marble statue" of him helped guide Stevens to the studio. The change did not do much to stem the decline as loyal listeners did not take to Stevens as they had to Kasem.

To further complicate matters, Kasem returned to radio the following January as Westwood One signed him to a contract. On January 21, 1989, Kasem became a competitor to the show he helped launch when Westwood One premiered Casey's Top 40, which used the weekly chart survey published by Radio & Records instead of the Billboard chart AT40 was still using. Many of the stations airing AT40 dropped it in favor of Casey's Top 40, causing another significant drop in listenership.

In an attempt to win back an audience, AT40 tried new features, including interview clips, music news, top 5 flashbacks, and previews of upcoming chart hits (called the "AT40 Sneek Peek"). It also stopped using the Hot 100 chart, switching first to the Hot 100 Airplay chart and finally to the Mainstream Top 40 chart. Later still, the countdown would use what was called a "No Nuttin'" gimmick that drew criticism; at various points of the show, a song would start immediately after the jingle for its position on the chart was played and Stevens would not offer any commentary until it concluded.

ABC kept American Top 40 in its syndication lineup despite the continued lack of improvement in ratings, but in 1994 the network finally decided to look elsewhere. ABC announced it would be acquiring the Rick Dees Weekly Top 40, which was using the same charts that Casey's Top 40 was, and that they would no longer carry American Top 40 as a result. The final AT40 for ABC aired on July 9, 1994, five days after its twenty-fourth anniversary. Radio Express, founded by original show creator Tom Rounds, kept AT40 in production following the move by ABC as the program was still carried in foreign markets. It was under Radio Express that the show finally came to an end nearly seven months later in the remaining markets that were carrying it, which by this point consisted entirely of overseas affiliates.

The very last original AT40 aired on January 28, 1995, and it ended with an extended last segment. As usual, the #2 song on the chart led it off; that song was "Another Night" by Real McCoy, which had been the #1 song one week earlier. Stevens then took a moment to thank the listeners for their support over the previous twenty-four plus years and played one last Long Distance Dedication, sent by him to the fans. After going into depth about his potential choices, Stevens revealed his selection to be "(So Tired of Standing Still We Got to) Move On" by James Brown. Stevens then gave a rundown of how many songs had been played over the series' entire run to that point, with a final total of 552 different chart toppers, including the one he was about to play as it returned to the top of the chart that week: "On Bended Knee" by Boyz II Men. As Stevens then read the credits and signed off for the final time, he played one final song. Perhaps appropriately, considering the circumstances, the song was "Happy Trails".

1998–2004: American Top 40 returns; second Casey Kasem era

Nearly three years after the cancellation of AT40, a series of events began that would result in the return of the long-running countdown to radio. Original host Casey Kasem had acquired the rights to the name and branding of his creation, but found Westwood One unwilling to exploit them. In addition, Kasem and his syndicator's parent company were in a salary dispute as Kasem felt he was not getting fair treatment while the syndicator believed the amount of advertising revenue Casey's Top 40 was generating did not justify Kasem's demands.

Since there was interest in Kasem, who was now 65 years old and hosting two adult contemporary countdown shows in addition to his pop show, Westwood One decided it was best for them to retain Kasem and in December 1997 he reupped for one additional year. However, he left Westwood One toward the end of February 1998 and gave no notice that he would not be back.

Chancellor Media, a forerunner of iHeartRadio, and Kasem began negotiations to relaunch AT40; Chancellor had just started a syndication service called AMFM Radio Networks and scored a significant coup by luring Kasem away from what had been a nine-year relationship with Westwood One. Although Kasem would eventually be taken to court by his former syndicator, the signing enabled him to reintroduce the American Top 40 name and brand to a modern audience. It also gave Chancellor the rights to the historic name as Kasem signed over his rights to the branding.

On the weekend of March 28, 1998, one week after Westwood One finally cancelled the three countdowns Kasem was hosting for them after four weeks without him. Chancellor also brought Kasem's AC countdowns to their network, with both now being branded as American Top 20.(see Spin-off programming below). Following the merger between Chancellor/AMFM and Clear Channel Communications (the predecessor of what is now iHeartMedia) in 1999, AT40 and other syndicated shows from AMFM Radio Networks were transferred into Premiere Radio Networks, which continues to syndicate the show as of today.

The resurrected American Top 40 kept the Radio and Records CHR/Pop chart previously used for Casey's Top 40 and was used as the basis for the show for the majority of this period. The only exception was a brief period from October 2000 to August 2001 when an obscure Mediabase chart was used. This chart had a rather ambiguous recurrent rule, which would see songs removed weekly from the chart from as high as #10. By the time Kasem's last show aired, the show had gone back to using Mediabase's charts.

Kasem's last show as host of AT40 aired on the weekend of January 3/4, 2004. His final #1 was Outkast's "Hey Ya!".

2004–present: Ryan Seacrest era

On January 10, 2004, Ryan Seacrest took over the hosting duties of American Top 40 from Kasem, although Kasem would continue to host American Top 20 and American Top 10 until his retirement in July 2009. With the host change, AT40 underwent a makeover, using a new theme song and introducing several new features. These extras included interviews with celebrities (which were not restricted to musical or countdown artists), a gossip section, and an update on movies screening in cinemas. Other extras inducted on a regular basis include "AT40 Breakout", a song predicted to crack the chart within the next few weeks (formerly known as the "Out of The Box" hit); "Request Line", a segment in which Ryan Seacrest will play a song requested by a listener; "Double Play", a former hit from the artist just played; "AT40 Sleaze" (inspired by the "Dees Sleaze" segment of the Rick Dees Weekly Top 40 radio show); and "AT40 Rewind", a hit song from the past decade or so. In between songs, Seacrest and his guest hosts often make deadpan one-liners while writers and producers can be heard laughing frequently, including the security guard "Roger". Additionally, Seacrest initially opened most shows by playing the previous week's #1 song, as Kasem often did in the 1980s; this was discontinued after 2006, but in mid-2009 Seacrest began including a shorter recap segment in the show's introduction, in which he would play brief segments of the previous week's top three hits. In December 2004, the Hot AC version of the show debuted, giving both Seacrest and Kasem competing countdowns in the same format until 2009.

The show also began using a new chart that used no recurrent rule. On the first show with Ryan Seacrest, this led to several older songs reappearing after having dropped off many weeks earlier. Over the long term, it meant songs could spend long runs for about a year on the chart even after they went to recurrent status on other published charts. "Here Without You" by 3 Doors Down set a longevity record in 2004 for the CHR show by lasting 50 weeks before finally falling off. In 2006, "Scars" by Papa Roach would go on to tie the record. In 2011, Taio Cruz set AT40's all time longevity record with his song "Dynamite". This hit remained on the chart for 72 weeks, from July 2010 to November 2011. On the Hot AC version of AT40, "Use Somebody" by Kings of Leon set the all-time record in 2011 at 117 consecutive weeks. American Top 40 also became more interactive, involving online song voting and e-mail. In December 2006, the series' website was revamped, and the online song voting was discontinued in favor of publishing the Hot AC chart. The website also includes a toll-free number where fans can make requests and "shoutouts", as they would to a local radio station, and by 2009 replayed clips of shoutouts became part of the show. Online song voting was later reinstated, with results of votes on American Top 40's website factored into the chart rankings. AT40 was also expanded to social media through Twitter and Facebook where listeners from around the world will request a song to be included in the AT40 Extra segment, as well as their own mobile application which is available for free download on the Apple AppStore for iOS devices and on Google Play for Android devices.

In March 2010, Premiere Radio Networks announced that "American Top 5," a condensed daily top-5 countdown, would begin airing as part of the daily radio program On Air, also hosted by Seacrest.

In March 2016, the show underwent some minor changes. "Tell Me Something Good", a segment from Seacrest's weekday show On Air, was added to American Top 40. Additionally, any "extra" songs that aired during the show are announced by Seacrest before playing. The following month, the show resumed mentioning some of its affiliates around the world during the show. AT40 also debuted a brand new custom jingle package produced by TM Studios of Dallas Texas, complete with chart number jingles and extra beds. The new package debuted early April 2016.

As of 2017, American Top 40 is produced by Claudine Cazian and engineered by James Rash.

Competition

American Top 40 has faced numerous competitors since its debut in 1970. Two of the longest-running have been the U.S. Music Survey, which was hosted by Dick Clark from 1978 until his 2004 stroke, and the Rick Dees Weekly Top 40, which has run continuously since 1983 with Rick Dees as host. Numerous other shows following the same format, both in the general top-40 category and in various specific radio formats, have aired over the course of AT40's history. Inn addition to Dees's show, Sean "Hollywood" Hamilton, Carson Daly, and the hosts at Radio Disney all host competing countdown shows targeted at the pop top 40 market.

AT40 flashback

From January 2001 to December 2002, many radio stations aired reruns of 1980–88 episodes under the title American Top 40 Flashback. The show was syndicated by Premiere Radio Networks. In its early weeks the shows were the original four-hour format of an American Top 40 episode, but after the first month and a half the show was reduced to three hours. Although American Top 40 Flashback ceased in December 2002, radio station WMMX in Dayton, Ohio continued to carry American Top 40 Flashback on Saturday mornings until the premiere of Casey Kasem's American Top 40: The 80s.

Casey Kasem's American Top 40—the 70s and 80s

On August 4, 2006, XM Satellite Radio began replays of the original 1970s and 1980s AT40 shows with Casey Kasem that were digitally remastered from the original vinyl LPs and open-reel master tapes by Shannon Lynn of Charis Music Group. The event began with a weekend long marathon of original shows, with AT40 then being added as a regular show on two of XM's Decades channels, "The 70s on 7" and "The 80s on 8". With the merger of Sirius Satellite Radio and XM Satellite Radio, these AT40 shows began airing on both services on November 15, 2008. On the 70s on 7, it replaced the 'Satellite Survey', a Top 30 countdown of 1970s hits, produced by Sirius and hosted by Dave Hoeffel. On the 80s on 8, it replaced 'The Big 40' countdown produced by Sirius and hosted by Nina Blackwood. As of October 11, 2009, Sirius XM replaced the AT40 countdown on 80s on 8 and debuted a revised version of 'The Big 40' countdown now co-hosted by four of the five original MTV VJs: Nina Blackwood, Mark Goodman, Alan Hunter, and Martha Quinn.

Sirius XM "70s on 7" currently runs AT40 each Saturday at 12PM with encore broadcasts the following Sunday at 9AM and at 12 midnight. Most show dates roughly correspond to the current week in real time. The mix of AT40 episodes being run on XM include the year-end countdowns, which are typically run in two parts: the first half (#100-#51) in one time slot, and then the second half (#50-#1) in the following time slot. The AT40 specials are also part of XM's rotation; for instance, "AT40 Goes to the Movies" aired prior to the 2007 Academy Awards, and on February 24, "The Top 40 Acts of the 80s So Far" aired on XM 80s the first week of July 2007. Also, "The Top 40 Songs of the Disco Era (1974–1979)" aired on Sirius XM "70s on 7" the second weekend of July 2011.

From October through early November 2006, oldies radio station KQQL in Minneapolis/St. Paul, which is owned by Clear Channel Communications, ran a series of American Top 40 episodes from the 1970s. Aside from one week, when the station attempted to air a four-hour episode from 1979 in the three-hour timeslot (resulting in the show getting cut off at #11 and the top 10 not being heard), this test run was largely successful. Because of the success, Premiere Radio Networks decided to launch "Casey Kasem's American Top 40: The 1970s" into national syndication featuring the three-hour shows from 1970 to 1978, and the last three hours of shows originally aired from October 1978 through December 1979. (One original four-hour program, first aired in October 1978, was edited into a three-hour program for reairing in 2007, and the four-hour "Disco Hits" special from July 1979 with the first hour optional was aired in 2008, but until the fall of 2010, no other program from the last 15 months of the 1970s was included in the "AT40: The 70s" package. Starting in late 2010, Premiere began airing three-hour versions of four-hour AT40s from 1978 to 1979, beginning the broadcasts at the start of the countdown's second hour; during the spring of 2012, Premiere began making the first hour of these programs "optional," meaning that stations can choose to air all four hours of the four-hour programs, or just the last three.) Starting in 2012, whenever programs from 1970 to 1972 were scheduled to air, Premiere began offering affiliates the option of airing a later 1970s program instead (typically, a corresponding year from seven years later, or 1977–1979).

The 1980s version premiered on April 8, 2007, replacing the American Top 40 Flashback reruns. The shows are available in either their full original four-hour format, or an abbreviated three-hour version that omits the first hour of the show. To date, the latest program to air as part of the "AT40: The 80s" package has been August 6, 1988 – Kasem's last show with the original program. Due to the rights to Shadoe Stevens-era episodes being held by Cumulus Media, no programs from August 13, 1988 to 1995 have been re-aired as part of this or any similar block.

To date, the only re-aired classic AT40 programs that featured a host other than Kasem are the shows of March 25, 1972 with Dick Clark as host, and September 12, 1981 with Gary Owens as host. Both have been aired as tributes after Clark's and Owens' deaths.

Newly produced extra segments hosted by voiceover talent Larry Morgan are available for use at stations' discretion. Prior to Casey leaving Premiere Radio, these segments were hosted by his son Mike; when the series first began, these segments were hosted by one of Casey's former guest hosts, Ed McMann. These extra segments are also heard on the 80s show. KQQL was the first to sign on, airing programs beginning on December 30, 2006. Typically, the "optional extras" were songs that had yet to enter the top 40 of the Hot 100. However, some songs never reached the top 40 but had since become popular at classic hits/oldies/classic rock stations, while others were tributes to performers who had just died. For early 1970s programs, some of the "optional extras" were actually extras (i.e., "oldies") that were originally a part of the original program; in this case, Kasem's original commentary and introduction of the song were kept intact, in lieu of Morgan's voiceover.

In March 2008, XM Satellite Radio rebranded the XM broadcasts with the "Casey Kasem's American Top 40" name and logo used for terrestrial broadcasts, although XM still aired the commercial-free broadcasts, while Premiere Radio carries edited and recut broadcasts with commercials. Following the merger of Sirius and XM, the AT40 shows airing on those platforms have occasionally been edited. In some cases, extras and LDDs have been cut from the original broadcasts.

Sirius XM 70s on 7 aired the inaugural AT 40 (which originally aired July 4, 1970) on July 4, 2013 as part of a special July 4 broadcast.

As of 2017, American Top 40: The 70s & 80s are produced by Toby James Petty and engineered by Shannon Lynn, both of whom had been members of the current AT40 production staff prior to Kasem's 2004 departure.

Billboard magazine

AT40 used the Top 40 portion of the Billboard Hot 100 singles chart from the show's inception in 1970 to November 23, 1991. The chart was widely regarded as the industry standard in tracking the most popular songs in the country, and was thus a natural choice to be used. Kasem would frequently announce during the show that Billboard was the "only" source for the countdown. While using these charts worked well for the first half of the 1970s, as music changed during the decade, and disco became popular on the charts, some rock stations began to drop the show because of complaints from program directors that AT40 was "playing too many songs not on their playlist."

This gradually became a wide schism as rock splintered into a half-dozen formats in the early 1980s. Historians have noted that no one station actually played all of the songs on the Billboard Hot 100 list, because they represented overlapping formats—hard rock, mainstream rock, heavy metal, dance, new wave, punk, rap, pop, easy listening/adult contemporary, country, and so on. Stations tended to specialize in only one or two of these formats, and completely ignore the others. As a result, AT40s weekly playlist could be very diverse in the styles and formats of the songs played.

One solution for the AT40 producers was to air frequent specials (at least three or four times a year) that concentrated on the classic music of the past, such as Rock in the Movies, Top Hits of the Seventies, and so on. But as Top 40 stations evolved into CHR, they began to avoid syndicated shows like AT40, preferring to stick with their own special niche formats.

By the early 1990s, many songs, mostly rap or heavy metal/grunge songs, would appear on the chart being fueled by singles sales, and had received low airplay; several were very long, others were too controversial or risqué for mainstream airplay (for instance, the very sexually explicit "Me So Horny" by 2 Live Crew made it to #26 on the Hot 100 in 1989). These songs would generally only be aired in brief snippets during the show.

Because of this, American Top 40 began using the Top 40 portion from the Hot 100 Airplay chart (then known as the Top 40 Radio Monitor) in lieu of the Hot 100. These songs generally scored much higher radio airplay, and some were not even released as singles (such as "Steel Bars" by Michael Bolton). During this time, a few songs made big debuts, including 2 that almost debuted in the #1 spot: "I'll Be There" by Mariah Carey, which entered American Top 40 at #4, and "Erotica" by Madonna, which entered at #2.

In January 1993, American Top 40 switched charts again, this time to the Billboard Top 40 Mainstream chart. This chart had more Top 40 Mainstream hits but fewer urban/dance/rap songs.

AT40 did not always use the official year-end chart from Billboard during the 25 years that they used their charts. In 1972 and 1973; in 1977; from 1980 to 1984; and again from 1990 to 1994, AT40 compiled its own year-end chart. These charts were very close to Billboard's, but AT40 would go with a mid-December to early-December time period where Billboard's survey year varied from year to year. AT40 matched Billboard's number one song of the year every time except in 1977, 1984, 1990 and 1993.

Radio & Records magazine

With the show's revival in 1998, a new chart was implemented, the top 40 portion of Radio and Records CHR/Pop top 50 chart, which was already in use on Casey's Top 40. This chart used a recurrent rule removed songs below #25 and had exceeded 26 weeks in the top 50; these removals, if they occurred in the top 40, would be reflected on the appropriate week's program. In 1999, the rule was modified to further restrict long chart runs. Songs falling below #20 with at least 20 weeks in the top 50 would now be removed.

On October 21, 2000 American Top 40 began using an unpublished chart on a weekly basis for the first time in its history. The chart seemed to be a variant of the CHR/Pop chart provided by Mediabase, the data provider to Radio & Records. The most noticeable feature of this new chart was its ambiguous recurrent rule. Songs would be removed regularly from within the top 15, seemingly regardless of the number of weeks it had spent on the chart. This chart lasted until August 11, 2001, when AT40 returned to the Radio & Records Pop chart. The return coincided with another modification in the recurrent rule; songs would be removed below #25 after 3 consecutive weeks without a bullet (an increase in radio plays). This change would be short-lived, and in November 2001, Radio & Records returned to the 20 weeks/below #20 rule, which remained in place for the remainder of Kasem's tenure.

Adult Contemporary countdowns (AT20 and AT10)

Beginning in the early 1990s, Casey Kasem also hosted two other shows counting down the top adult contemporary hits of the week. These moved with him after he left Westwood One and Kasem kept doing them after he handed AT40 over to Ryan Seacrest in early 2004.

Kasem's countdown for Mainstream and Soft Adult Contemporary radio stations debuted in 1992 under the name Casey's Countdown. Originally Casey's Countdown consisted of 25 songs, but in 1994 it was shortened to 20. With the revival of the AT40 brand name, the AC chart became American Top 20. In March 2004, the Mainstream AC edition was shortened again, this time from twenty to ten songs, and became known as American Top 10.

Another show for hot adult contemporary radio stations debuted in November 1994, since the Hot AC or "Adult Top 40" format was rapidly growing in popularity at the time. The original name of the show was Casey's Hot 20. Like its sister Mainstream AC show, it, too, was renamed American Top 20 once AT40 was relaunched (resulting in two different shows being entitled American Top 20).

The AC shows were three hours in length and included many AT40 staple features, including chart "extras" and Long Distance Dedications (known as "Requests and Dedications" during the Westwood One years), as well as spotlight features on number one hits of each chart week from years past. AT10 continued to feature Long Distance Dedications, and some additional features that were staples on the original AT40 were re-added to both shows during Casey's final years, including the "Book of Records" and "Whatever Happened To...?" AT10 also featured additional chart extras under the banner of "AT10 Spotlight," built around a particular theme (the theme for the first week of the revamped AT10 in 2004 was "Band Members Gone Solo").

As with the Top 40 show, both Casey's Countdown/AT20/10 AC and Casey's Hot 20/AT20 Hot AC initially used the AC charts published by Radio & Records from their inception until 2003, except for a brief period in 2000–2001 when both used unpublished Mediabase 24/7 charts. From 2003 to August 2006 (when R&R stopped using Mediabase to compile its charts), both shows used the Mediabase charts. From August 2006 until the end of its run, the AC shows once again were based on unpublished charts.

In 2005, WLTW in New York City commissioned a shortened one-hour version of American Top 10 featuring only the current hits of the week and omitting the Long Distance Dedications, AT10 Extras, and Spotlight features.

In December, AT10 focused on Christmas music because many of its affiliates broadcast a holiday/Christmas music format around the holiday season.

Kasem retires

Shortly after Premiere Radio Networks announced it would not renew AT20 or AT10 when Kasem's contract expired, Kasem put out a press release announcing his retirement from radio after the weekend of July 4, 2009.

Both shows opened with Kasem remarking that it was the thirty-ninth anniversary of his first countdown before telling the audience that the upcoming countdown would be the last. Both shows featured one final Long Distance Dedication from a fan thanking Kasem for all he had done over the years and requesting "Thank You For Being a Friend" as his song. The final Spotlight feature on AT10 focused on artists with some of the most top ten hits of the era.

When the countdown on both shows reached its end, instead of telling a story about something connected with the song or the artist behind it, Kasem instead chose to use that time to offer a brief history of how his career hosting AT40 and its spinoffs unfolded. This was followed by the trademark drumroll and Kasem's introduction of the lone remaining song to be played. Shinedown's "Second Chance" was the final #1 song on American Top 20 after spending the final three weeks at the top of the chart and Taylor Swift's "Love Story" earned that spot on American Top 10 for a fifth consecutive week. Once the song(s) ended, Kasem recapped the song title and how long it had topped the chart as he had done for years. He then closed both shows with the following farewell speech.

I'd like to share with you something I've learned over the years. Success doesn't happen in a vacuum. You're only as good as the people you work with, and the people you work for. I've been lucky; I've worked for and with the very best!

Kasem then read the end credits and closed the show for the last time with his trademark signoff.

The following year, Casey's daughter Kerri Kasem joined the Premiere Radio family, as Premiere debuted The Side Show Countdown, which she co-hosted with Mötley Crüe's Nikki Sixx. She left the program in 2013.

Television spinoff

From 1980 to 1992, a video version of the show entitled America's Top 10 was aired in syndication to television stations across the United States. Kasem hosted this version from 1980 to 1989. When Kasem left American Top 40 in 1988, he remained as host of America's Top 10 until the end of 1989, when he would be replaced by Siedah Garrett and later Tommy Puett. Kasem returned by 1991, and the show ran until 1992.

Other formats

Based on the success of American Top 40, Kasem and Don Bustany created a spinoff top 40 countdown for Watermark for Country Radio called American Country Countdown, patterned after Kasem's program. "ACC" premiered in 1973, and was hosted by Don Bowman until 1978, then by Bob Kingsley until 2005 when Kix Brooks of the late country music duo Brooks & Dunn took over, and has been doing so since. Kingsley now hosts a separate countdown, Country Top 40 (abbreviating, not coincidentally, as "CT40"), which follows the same format as AT40 and ACC.

After Kasem left ABC, the network launched American Gold, a spinoff oldies countdown (featuring far fewer songs, and often focusing on a particular artist) hosted by Dick Bartley. American Gold's last show aired at the end of March 2009, replaced with another show hosted by Bartley for United Stations Radio Networks, Classic Countdown.

The American Top 40 format was adapted in an Australian show titled Take 40 Australia, similarly counting down the top 40 songs in the country.

Censorship, offensive songs and affiliate standards

American Top 40 airs radio edits for American (and international) radio stations, no matter what the country it airs in.

Casey Kasem and Watermark's policy regarding putting American Top 40 together was to always play the 40 most popular songs in the United States and never to ban a record from the countdown. However, whenever songs with potentially offensive lyrical content made the top 40, Watermark would send out memos to affiliated stations alerting them of the presence of that song in the countdown and sometimes provide stations with suggestions on how to edit the song out of their AT40 broadcasts. The first song to receive this advisory was in April and May 1971, with a spoken word piece, "The Battle Hymn of Lt. Calley", by Terry Nelson and C-Company. Some more well-known songs which received this treatment included "Kodachrome" by Paul Simon, "Roxanne" by The Police, "Ain't Love a Bitch" by Rod Stewart, and "Paradise by the Dashboard Light" by Meat Loaf.

Perhaps the most infamous of these songs was Chuck Berry's number-one hit "My Ding-a-Ling", which put some stations in the odd position of having to air AT40 without playing the number one song; at least one station, KELI in Tulsa, Oklahoma, censored out the song at its #1 position, replacing it with a message from station management, explaining why they chose to censor the program. The censorship of this song continues even today as some stations, such as WOGL in Philadelphia, replaced this song with an optional extra when it aired a rerun of the November 18, 1972 broadcast (where it ranked at #14) on December 6, 2008.

In the summer of 1977, radio station KRNQ in Des Moines, Iowa, edited out "The Killing of Georgie" by Rod Stewart, because of the subject matter of a homosexual being murdered; that song peaked at #30 on the countdown.

Another example of this policy dates from 1978, when Billy Joel's "Only the Good Die Young" was on the charts. Because of the nature of the song (Joel singing about urging pre-marital sex by a teen Catholic girl, Virginia), AT40 had placed warnings in shipments to warn affiliates in highly Catholic populated areas along with a special break in the countdown for stations to substitute another song in its place. The affiliates usually used the suggestion, though some did not and no major complaints were ever heard. Many of these memos have been reprinted in Pete Battistini's book, "American Top 40 with Casey Kasem (The 1970s)."

In situations where a charting song contained offensive language and the record company was unable to provide AT40 with a clean edit of the song, the producers would often make an edit themselves. Such was a case with Bob Dylan's Top 40 single, "George Jackson", which peaked at #33 in January 1972 and appeared for two weeks on AT40. The offensive lyric in the song was, "He wouldn't take shit from no one." To rectify the problem, AT40 engineer Bill Hergonson edited the lyric, which was now heard as "He wouldn't take it from no one." A similar situation occurred again in July 1975, when The Isley Brothers' Fight the Power was in the Top 40, but in this case, the substitute version provided by the group's label was unsuitable, resorting to the engineer to substitute grunts and extra drum beats over the offending parts of the original record. However, this was not before AT40 erroneously played the uncensored version (with the lyric "...by all this bullshit goin' down") the first two weeks on the chart, on the July 12 and 19, 1975 editions.

Although Kasem and his crew never banned a song from airplay on the countdown, there was at least one instance in which both Kasem and his guest host, Charlie Van Dyke, refused to announce the title of a song on his show. When George Michael's "I Want Your Sex" hit the Billboard charts in the summer of 1987, Kasem and Van Dyke refused to announce the name of the song; only its artist (e.g., "George Michael's latest hit is up five notches this week..."). Also, as had been done with previous controversial hits, because of the song's suggestiveness, the show's structure was altered slightly, so stations could opt out of the song. This pattern was also evident during the 1987 Year End countdown. The song title was mentioned five times during its chart run (June 20, 1987; June 27, 1987; April 7, 1987; December 9, 1987 and September 19, 1987), during the week-ending episode of September 26, 1987, when it dropped out of the Top 40, and during the Top 100 of 1987 show; Shadoe Stevens, his successor, however did mention the title on the show from July 31, 1993 as part of the Flashback feature, as it was in the top 5 from that week in 1987. In the spring of 1991, when "People Are Still Having Sex" by LaTour and "I Wanna Sex You Up" by Color Me Badd debuted the same week, their titles were announced in full.

Another song that had its title unannounced after its first week was "Me So Horny" by 2 Live Crew, in the fall of 1989 [the Shadoe Stevens era]. It was mentioned twice at the beginning of the song, and back announced once, its debut week. For the rest of its chart run, the title was never again mentioned. When the 2 Live Crew returned to the top 40 in the Summer of 1990, with "Banned in the U.S.A.", Shadoe did mention that it was the follow-up to "Me So Horny". The song did come with edit out instructions for stations as well. Other songs around that time with edit out warnings were "The Humpty Dance" by The Digital Underground, and "Tic Tac Toe" by Kyper.

Very rarely was a song on that week's chart excluded from that week's AT40, if so only due to time considerations—on an edition that aired the weekend of December 19, 1970, The Guess Who's "Share the Land", which ranked at #30 that week, was omitted from AT40, in order to play both sides of that week's #1 Double A-side hit, George Harrison's "My Sweet Lord" / "Isn't It a Pity". Normally when a Double A-side appears on the charts, one side is played one week, with the other played the next week, alternating each week as long as it was in the Top 40. Similar omissions occurred in February 1974 when both the Gordon Sinclair and Byron MacGregor versions of The Americans simultaneously hit the Top 40; in each case, only one version was played each week alternately.

As has been mentioned previously, many rock radio stations in the late 1970s adopted anti-disco stances, and this, too, was reflected in the way some affiliates edited AT40. For example, one 1979 show featured a story about disco saving New York; again, the show was structured so that anti-disco stations could edit the story out of the show. (Notably, Kasem ended the monologue with the prediction that "disco is here to stay," which was proven false in short order, as disco rapidly fell out of fashion by 1980.)

More famously, on the weekend of July 7–8, 1979, Cleveland, Ohio AT40 affiliate WGCL (now WNCX), instead of carrying the "American Top 40 Top 40 Disco Songs" special because of being an anti-disco radio station, did its own version of American Top 40 using the July 7, 1979 Billboard chart as the source with Townsend Coleman handling the hosting duties for Casey Kasem. The special Cleveland-only American Top 40 episode did not feature the AT40 Archives, extras, or Long Distance Dedications – just the top 40 singles of that week, which was preceded by a recap of the previous week's top three. Because the station did not have disco songs in the playlist, and the top 40 that week had several disco songs, WGCL had to reach outside its library to find copies of some of the songs, some of which were not the single versions; "Hot Stuff" and "Bad Girls" by Donna Summer, the songs occupying the #3 and #2 spots on the Billboard chart for that week respectively, were conveniently available as a 12-inch medley, which Coleman used for the show. Through clever editing, Coleman also took the "Casey's Coast to Coast" jingle (pronounced "K-C's Coast to Coast") and spliced in a "T," to provide an appropriate "TC's Coast to Coast" jingle. Kasem did not learn about the deception until 1996, laughing the whole thing off by saying, "Maybe I don't want to hear it!"

Coleman's sleight-of-hand was actually the second time a version of the AT40 had aired that was not quite on the up and up. According to Rob Durkee's book "American Top 40: The Countdown of the Century", Dave Morgan of WDHF (now WEBG) in Chicago ghosted an edition of the program sometime in the summer of 1975. When the station's copy of the show did not arrive in time, he used Billboard's list and merely played the records, apparently heavily implying that the show was American Top 40 without actually identifying it as such. "My program director made me do it!" Morgan said years later. The following year, WDHF would refuse to play AT40's "Fourth of July's Greatest Hits" special, due to the special's overabundance of #1 hits from the pre-rock era. But while the special was a stark departure from the contemporary sound of the 1970s, Tom Rounds in his press release reminded stations that it was the United States' "one and only bicentennial."

From 1992 to 1994, two radio stations still carrying American Top 40 had to carry customized versions of the show. WPLJ in New York City aired the show with the urban/dance/rap songs mentioned but not played and were replaced here and there by Hot Adult Contemporary leaning extras. KUBE in Seattle, Washington aired AT40 with a few songs that did not fit the station's Top 40 Rhythm format omitted each week. It has also been reported that WSTR in Atlanta, Georgia, being an anti-rap station and a very Adult Contemporary-leaning CHR, edited "Another Night" by Real McCoy (a Euro disco record with rap breaks) out of its broadcasts of Casey's Top 40 in 1994, even while the song was at #1 on the show (which used the Radio & Records CHR/Pop chart).

Songs with offensive words in their titles were often censored for radio airplay, and is reflected in their inclusion on AT40. In 2010, three such songs have made it to the #1 position on AT40: "Fuck You" by CeeLo Green (changed to "Forget You"), "Fuckin' Perfect" by Pink (changed to "Perfect"), and "Tonight (I'm Fuckin' You)" by Enrique Iglesias (changed to "Tonight (I'm Lovin' You)"). Other notable songs included "Niggas in Paris" by Jay-Z & Kanye West (becoming "In Paris", peaking at #5), "Ass Back Home" by Gym Class Heroes (became "Get Yourself Back Home", peaking at #12), "I Don't Fuck With You" by Big Sean featuring E-40 (became "I Don't Mess With You," peaking at #34), "Fuck U Betta" by Neon Hitch (becoming "Love U Betta" and peaking at #29; this song was also first played in Subway's Fresh Buzz Song of the Week).

In early 2013, Justin Timberlake's single "Mirrors" had to be edited for time, as the song is over 8 minutes long.

In 2015, The Chainsmokers's "Roses" (feat. Rozes), Travis Scott's "Antidote", Halsey's "New Americana", and Alessia Cara's "Here" had been edited by censoring one of their chorus in the lyrics dealt with prohibited drugs.

Special Countdowns

Occasionally American Top 40 airs special countdowns in place of the regular American Top 40 countdown show. These included¹:

Annual Countdowns

Additionally, the top songs of the year were counted down at the end of every year. In 1970 and 1972, AT40 counted down the year's top 80 hits. In 1971 and 1973, only the top 40 was counted down due to AT40's top 40 Christmas Countdowns those two years.

Beginning in 1974, the top 100 songs of the year were counted down and was done so every year with few exceptions. The year-end shows were counted down over a two-week period, although stations could edit the shows into one long special, with special instructions on how to connect the two parts together. Beginning in 1983, a single eight-hour special became the norm. In 1992, the year end countdown was temporary back to its two-week format, in 1994 (the last year of the old AT40) the year end countdown was only 50, and with the AT40 return in 1998 the year end countdowns were the two-week format (except for 1999 when it counted down that year's Top 50 songs).

In 1979, AT40 presented the top 50 songs of that year and followed it the following week with the top 50 songs of the 1970s. This was done again in 1999, except only the top 40 of the year and decade were aired in respective weeks. In 2009, the year-end countdown took place in the usual two-week-long format, with the top 100 songs of the year being counted down, but in the first week of 2010, the top 40 songs of the decade were counted down. Since the end of 2010, the year-end countdown has been downgraded to only top 40 songs which took place on the final weekend of year, and repeatedly on the first weekend of the new year with additional extras.

During the run of "American Top 20" and "American Top 10," an updated Christmas countdown, the "Top 60 Christmas Songs," would air annually the two weeks immediately preceding Christmas.

Substitute hosts

Over 50 celebrities—among them radio personalities, game show hosts, and (particularly since Ryan Seacrest took over hosting duties) charting artists—have substituted for these three throughout the show's run. Radio announcer Charlie Van Dyke filled in for Casey a record 31 times in the 1980s.

Substitutes for Ryan Seacrest have included:

Some well-known guest hosts for Casey Kasem have included:

Los Angeles deejay "Emperor" Bob Hudson attempted to substitute for Casey sometime between 1976 and 1978 (no specific date was given); however, Hudson had trouble recording his material for AT40, giving up after realizing that he could not host AT40 the same way he would host his morning drive show. As a result, Casey cancelled his vacation and returned to Los Angeles to record that week's AT40, but made sure that Hudson, a legendary disk jockey and comedian, got paid for his work anyway.

Guest hosts for Shadoe Stevens included:

¹ The week Jay Thomas hosted, October 31, 1992, Chris Cox of KEZY in Anaheim, California (now KFSH-FM) taped a special version for that station at Watermark's studios, because of contractual stipulations that prohibit talent from Los Angeles-based stations from being heard on KEZY (Thomas was still employed at rival KPWR at the time).

Notable songs played on American Top 40