This web page produces a numerical table of monthly latitude
insolation at top-of-atmosphere for a given calendar year. Because a
tropical year is assumed to be 365.2425 days long, the calculations may
not be precise a few centuries from 2000 AD. On the other hand, using
Berger's orbital parameters, the table can show what past of future
insolation will be for other epochs.
SRMONLAT.FOR is the Fortran source code
of the program used on this web page.