David and Jennifer Risher are challenging fellow philanthropists to give more of their money away.
The Urban-Brookings Tax Policy Center says only about 10% of households now have an incentive to donate.
"The bank had shut us down and we didn't know how we were going to go forward."
"We're getting a distorted capitalism that does not produce shared prosperity," says Walker.
They blame the 2017 tax bill.
Many Americans had less of an incentive to give, as the law doubles the standard deduction.
Collins, author of "Born on Third Base," joined us to talk about the country's wealth gap.
Charities overheads differ starkly but may not be a big determinant of who gives.