Fifty-five years after the the United States passed the Equal Pay Act, women in the US still face a substantial gender wage gap. On Tuesday, the country is recognizing Equal Pay Day, which was established in 1996 to highlight this disparity.

Today, on average, an American woman earns around 80 cents for every dollar a man earns, and women's median annual earnings are $10,500 less than men's, according to a recent report by the Senate Joint Economic Committee Democratic Staff.

But that gender wage gap can vary widely depending on the location.

The map below shows which US states have the most and least severe gender wage gaps. Using US Census Bureau data from 2016 (the most recent year available), it compares the median earnings of men to those of women.

In Wyoming, the gender wage gap is 36%, the biggest in the nation. Twenty-three states in the country currently have gender pay gaps that are larger than the national average of 19.5% — though that's down from 32 states in 2015. The narrowest gender wage gap exists in New York and Delaware, where women earn 89% of the median salary for men.

The gender wage gap is even wider between white men and women of color. In Maryland, for example, Hispanic women tend to earn just 49% of what white men make.

Most states have implemented laws against gender discrimination, and all but three states (Arkansas, North Carolina, and Tennessee) have laws prohibiting employers from discriminating on the basis of gender.

While progress has been made towards pay parity between men and women, the Institute for Women's Policy Research predicts that wages will not be equal until 2059.

Find the article here.