The Mint struck Kennedy half dollars in large numbers in an attempt to meet the overwhelming demand. The Treasury had initially planned to issue 91 million half dollars for 1964, but raised the number to 141 million. However, a public announcement of the increase failed to cause more coins to actually circulate or to decrease the prices on the secondary market. By late November, the Mint had struck approximately 160 million pieces, yet the coin was almost never seen in circulation. Silver prices were rising, and the majority of the coins were being hoarded. Hopeful that issuing more 1964-dated coins would counter the speculation in them, the Treasury requested and received Congressional authorization to continue striking 1964-dated coins into 1965. Eventually, almost 430 million half dollars dated 1964 were struck, a sum greater than the total struck for circulation in the sixteen years of the Franklin half dollar series.