The CEOs of Uber, American Airlines, LinkedIn, and Microsoft are among hundreds who have signed an open letter to states calling for computer science courses to be required for graduation.

The letter cited a Brookings Institution study that found that students who have taken a single high school computer science course see an 8% increase in their wages, regardless of their chosen career. The letter projects that mandating computer science courses across all 50 states could unlock $660 billion in earnings for “everyday Americans.”