The 1951-S Jefferson Nickel has one of the lower mintages for the circulation strike series. Only the 1938-P, D, 1939-D,S, 1949-S, 50-P, 50-D, 51-S, and 1955-P have mintages under 10 million.
The 1951-S appears to be scarce in MS66 grade and higher. Less than 500 examples have been confirmed by PCGS in MS66 condition, with less than handful known in MS67. Examples in MS66 displaying Full Steps are even scarcer with less than 3 dozen known by PCGS and none existing in any higher condition with the Full Steps designation.