During the period of the first U. S. Mint (1792-1833) the coinage figures were reported in a manner that is confusing to researchers today. In addition the Mint had a practice of utilizing dies until they failed, regardless of the date they bore. Incoming Mint Director Robert M. Patterson prohibited the use of obsolete dies around 1835, though the Mint's figures are still subject to interpretation, as it operated on a fiscal year rather than the calendar one. As Roger noted, the dates these coins bore was irrelevant to the Mint's accounting, making it difficult to be certain of how many coins were produced for specific dates.