best CD "of the year" compilations?

    I'm interested in buying music CD's featuring music from roughly the
years 1945 to 1965.  I'm mostly interested in the top 20-40 hits of each
year, not just someone's idea of what 20 songs from the year they want
to include.

   I've seen "Reader's Digest" collections, "Hollywood Hit Parade"
collections, Billboard top rock & roll of the year, Great Songs of
(insert year here), and others.

   Anybody have any experience with which collections are most complete
(considering the years), and which ones actually include the most
popular songs of each year?

   Thanks!  I'd prefer not to have to buy multiple different CD's for
each year in order to get the top 20 from each year.