Today’s daily viz from Derek Lieu, a web producer at The Chronicle of Philanthropy:

The number of charities and foundations in the United States reached nearly 1.3 million in 2010, representing a 150 percent growth over the last 20 years. This visualization charts the changes to the tax-exempt sector since 1991 using data released by the Internal Revenue Service. Click on the INFO box to learn how to use this tool.

Follow Derek on Twitter.