In a refocused effort to reduce the federal budget deficit, legislators in both parties have apparently proposed changes to the charitable tax deduction, which some say could cost nonprofits $9 billion a year in reduced donations. In conjunction with the Charitable Giving Coalition, the American Alliance of Museums has now joined other nonprofits to declare November 20 as “Protect Giving Day.” The groups will meet in Washington, D.C. on Wednesday for congressional meetings, luncheons, and panel discussions about the “cascade of consequences.”