The data for the "SEER AYA Site Recode" algorithm was taken from the SEER website:

https://seer.cancer.gov/ayarecode

ayarecodewho2008.txt
The data was taken as-is (the downloadable ASCII version); no post-processing.

ayarecode-2020revision.csv
The ASCCI download was replaced with an Excel download, the file was saved
as CSV and the "-" special dashes were replaced by ASCII dashes.