The Códice de Santa María Asunción is mid-16th century Mesoamerican pictorial codex, containing censuses of twelve rural communities in Tepetlaoztoc.
Analysis of this codice along with Codex Vergara have revealed details of a complex land survey system utilized by the Aztecs including the ability to calculate the areas of irregular plots of land.
References
Códice de Santa María Asunción Wikipedia(Text) CC BY-SA