This Friday is the anniversary of the Lilly Ledbetter Fair Pay Act of 2009, a reminder that a significant pay gap still exists between men and women in the United States. At the median, hourly pay for women is only 82.9 percent of men’s median wage ($15.21 versus $18.35). While over the last several decades women have made gains in terms of education attainment and labor force participation, compared to men, they are still paid less, are more likely to hold low wage jobs, and are more likely to live in poverty. This economic gap exists to a greater degree for women of color and remains persistent across women of varying education levels and working in different occupations.

But the gender wage gap is only one way the economy shortchanges women. At the same time the gender wage gap has persisted, hourly wages for the vast majority of workers have stagnated, as the fruits of increased productivity and a growing economy have accrued to those at the top. It hasn’t always been this way: pay rose with productivity in the three decades following World War II. But since the 1970s, pay and productivity have grown further apart, as the result of intentional policy decisions that eroded the leverage of the vast majority of workers to secure higher wages.

A progressive women’s economic agenda, one that seeks to truly maximize women’s economic potential, must focus on both closing the gender wage gap and raising wages more generally.

The bottom line on the figure below shows the median hourly wage for women from 1979 to 2014. As you can see, women’s hourly wages have risen slightly over the last 35 years, while men’s hourly wages (the blue line) have dropped. So the gender wage gap has narrowed, but 40 percent of that narrowing occurred because men’s wages fell. This is the wrong way to close the gender wage gap. Gender wage parity does not improve women’s economic prospects to the greatest possible extent if wages for men and women remain equal but stagnant in the future.

Meanwhile, the green line in the figure represents the amount overall wages could have risen over the last 35 years. If the gains to a growing economy hadn’t disproportionately gone to the top, then there would have been plenty of room for the gender wage gap to close while both men’s and women’s wages increased. In fact, if we had closed both the gender wage gap and the productivity pay gap, women’s wages today would be 70 percent higher.

To maximize women’s economic security and raise wages, we must pursue policies that intentionally tilt bargaining power back toward low- and moderate-wage workers, and we must end discriminatory policies that contribute to the gender wage gap. We should close the gender wage gap by “leveling up”—spurring women’s wages to catch up to men’s while both men and women share in overall growth.

The Lilly Ledbetter Act has been absolutely essential in helping to close the gender wage gap, but it’s not enough. Only when we take a holistic approach to women’s wages and seek to close both the gender gap and the inequality gap will women reach their potential in the economy.