Hiya,
There is NO specific USPAP requirement for any sales history on comps. However, Fannie Mae has a requirement that specifies a one year history on the comps.
Because Fannie is a GSE, they have the right to add requirements and these become supplemental standards.
So, for the subject, you must report and analyze a 3 year history and for conforming loans, a 1 year history for the comps.
That said, it is a good idea to go back 3 years on the comps as well. This data is available from the same source you would use for your one year history. It can be particularly helpful to a UW or reviewer in markets with rapidly rising prices because prior sales of the comps, when shown, can demonstrate price increases that may be applicable to the subject.
Hope that helps,
Brad Ellis, IFA, RAA