Mr T, Freeman's survey results are published in his first book The Victorian Bronze Penny (1860-1901). The was privately published by Freeman in 1964 (and again in 1966 as a second edition, which was essentially the same). The survey covered some 50,000 circulated Victorian bronze pennies, of which 15,653 were bun pennies with readable dates. These were mostly acquired via an arrangement where Freeman went through coins collected by a Scottish bus company. This helped insure that they were a fairly random sample of coins that were in circulation before the great interest in pre-decimal pennies that started with decimalization. This is by far the largest survey conducted that I know of, and can never be repeated. This became the basis for Freeman's rarity ratings in his later books. These slim books with only about 38 pages, are scarce today. You might be able to find a copy in a library. Best Regards, InforaPenny