Subway riders have bought millions fewer MetroCards since the MTA added a dollar surcharge on each new card to cut down on the number of cards produced, officials announced Monday.

Straphangers purchased 25 million MetroCards between March 2013 and April 2014 — a 71 percent drop from the 91 million purchased over the same period the year before.

The MTA had proposed the surcharge to encourage riders to refill their MetroCards, which cuts back on the number of cards that need to be printed. The MTA took in $24 million in revenue from the surcharge and saved $3 million from the expense of printing and stocking the cards.