from page 20 and is "estimated number of surviving examples in all
grades, both attributed and not". But to take other examples, the 1836
B5 quarter is widely regarded as R6, in one of the quarter books "15-17
known". In the latest dime census, the 1820 JR12 is listed as R6 with 17
reported. My first thought is, "these are actually R5+ die marriages".