The 1955-S Roosevelt Dime has one of the lower mintages in the series. Only three coins in the 1946-1964 silver dime series have a lower mintage. The 1955-P has the lowest mintage, the 1949-S has the second lowest, the 1955-D has the third lowest and then the 1955-S come in in fourth place as far as lowest mintages.
For the most part the 1955-S Roosevelt Dime is very common in circulated grades and up to MS65 condition. In MS66 condition it becomes a little more difficult to obtain but there are still thousands in existence. In Ms67 condition it becomes scarce with possibly no more than a few hundred known. In MS68 it is almost no existent with the exception of one sole example graded PCGS MS68 and none being finer.