Betsy Ross, Amelia Earhart, and Rosa Parks could all be contenders for appearing on US currency.

 

First, it helps to be a titan of American history, like former presidents George Washington, Abraham Lincoln and Andrew Jackson, or founding fathers Benjamin Franklin and Alexander Hamilton.

 

The current Secretary of the Treasury is responsible for selecting the lucky few featured on US bills, and though the bills have been frequently redesigned for security purposes, the famous faces on them have remained the same since 1929.

 

That's when a special treasury committee selected them due to their "permanent familiarity in the minds of the public", according to the US Department of the Treasury.

 

Thanks to one 19th Century upstart（暴发户）, one also must be dead to appear on a bill.

 

"Some lowly clerk put his image on currency during the Civil War," says currency expert Frederick Bart. "People decided he had no right to be there, so that changed our laws forever."

 

Though acclaimed women such as suffragette Susan B Anthony and Native American guide Sacagawea have appeared alongside men on US coins, only one has ever graced a printed US bill.

 

That singular honour goes to the nation's first first lady, Martha Washington.

 

Mrs Washington was featured alone on the face of the $1 silver certificate in 1886. Ten years later, she was moved to the back of the bill and featured next to her husband, George, with the roman numeral I between them.

 

It may be years until a woman makes it onto a bill again, says Bart. She would have to have a major political impact, such as assuming the presidency, and then die in order to even be considered, he says.

 

Terry O'Neill, president of the National Organization for Women, says the time to see women represented on US currency is now. She says abolitionists（废奴主义者） Sojourner Truth and Harriet Tubman or politicians Bella Abzug and Shirley Chisholm already, in a manner of speaking, fit the bill.