The U.S. Mint launched its state quarters program in 1999 as a way to honor unique contributions by each state. The program ended in 2008 and, now, some of the quarters are harder to find than others.

During production, the U.S. Mint issued five new quarters each year released in the order the states ratified the Constitution or were admitted to the Union. The “heads” side of the quarters show the familiar portrait of George Washington that’s been used on the quarter since 1932. The reverse side – or tails side – of each quarter features a design related to that state.

The designs include things like the Statue of Liberty for New York, the Louisiana Purchase and a pelican for Louisiana and the spike uniting the Central Pacific and Union Pacific railroads in Utah. Alabama’s quarter, issued in 2003, includes an image of Helen Keller with her name in English and a reduced-size version of Braille, along with an Alabama long leaf pine branch with magnolias gracing the side of the design.

Not all of the state quarters are available in the same amount, however. KHON2 recently reported that quarters were produced to meet Federal Reserve demand at the time. In all, some 34.3 billion 50 state quarters were produced with an average of 400 million each. For some, according to the report, more than 1 billion of the coins were produced.

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Virginia had the most quarters produced – 1.6 billion. Seven other state quarter designs had more than 1 billion issued: Connecticut, Maryland, Massachusetts, New Hampshire, New York and North Carolina.

Based on the number printed and the amount currently in circulation, the quarters that may be hardest to find include:

• Oklahoma: 416.6 million minted
• Maine: 448.8 million minted
• Wisconsin: 453.2 million minted
• Missouri: 453.2 million minted
• Alabama: 457.4 million minted

Other states with less than half a billion minted include Arkansas, Florida, Illinois, Iowa, Michigan, Minnesota and New Mexico.