For the first time in nearly 97 years, the price of a stamp is set to go down.

On April 10, a first-class stamp will cost 47 cents, down from its current 49-cent price.

The reduction is part of a pre-arranged agreement with Congress. The Post Office got to increase the price of stamps by 3 cents in 2014 to help it raise $4.6 billion in revenue. But the price hike was only set to last two years. (It gets to keep one cent of the increase to keep up with inflation).

The Post Office is practically begging Congress to let it keep stamps at 49 cents. It says rolling back prices to 47 cents will cost the already badly bleeding Post Office $2 billion a year.

"Removing the surcharge and reducing our prices is an irrational outcome considering the Postal Service's precarious financial condition," said Postmaster General Megan Brennan in a prepared statement. "Our current pricing regime is unworkable and should be replaced with a system that provides greater pricing flexibility and better reflects the economic challenges facing the Postal Service."

Congress has pegged stamp price increases to inflation, which has barely budged over the past decade.

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The Post Office is still reeling from the Great Recession, when its sales fell by $7 billion in 2009 alone. The Postal Service says that package volume is way up over the past few years, but it's "not nearly enough to offset the decline in revenues" from first-class mail.

Standard mail, such as first-class letters and postcards, make up 76% of the Postal Service's sales -- all of which have prices capped by Congress.

Postcard stamp prices will drop by a penny to 34 cents, and international stamps will cost $1.15, down from $1.20.

There's hardly anyone alive who remembers the last time the price of a stamp fell. That was in July 1919, when first-class stamp prices dropped from 3 cents to 2 cents.