The piece was struck by the tens of millions, at all three mints (Philadelphia, Denver and San Francisco), through the remainder of the 1910s. In 1921, a recession began, and no nickels at all were struck the following year. The low mintage for the series was the 1926-S, at 970,000 — the only date-mint combination with a mintage of less than 1 million. The second lowest mintage for the series came with the 1931 nickel struck at the San Francisco Mint. The 1931-S was minted in a quantity of 194,000 early in the year. There was no need for more to be struck, but Acting Mint Director Mary Margaret O'Reilly asked the San Francisco Mint to strike more so that the pieces would not be hoarded. Using materials on hand, including the melting down of worn-out nickels, San Francisco found enough metal to strike 1,000,000 more pieces. Large quantities were saved in the hope they would become valuable, and the coin is not particularly rare today despite the low mintage.