In a fascinating new study, Chattanoogans came out as extremely generous. The study of tax filings released Monday showed that Chattanoogans on average donated at least 50% more of their disposable income to charities and religious groups than did the typical American.

Those in Chattanooga think there are easy explanations, but it’s still a bit of a mystery why these numbers are what they are. As Pete Cooper, president of the Community Foundation of Greater Chattanooga said, “Chattanooga is a generous town and continues with a culture of giving from people of all income levels. Among the wealthy, there has long been a philosophy of charitable giving which helped establish some of the state’s biggest foundations here decades ago. But among low- and middle-income families there is also a commitment to giving because I think our citizens recognize the needs around them and they understand where their gifts go and help out.”

As Eva Dillard, president of the Chattanooga United Way said, “Obviously, during the recession, we had some struggles but Chattanooga has always been known for its philanthropy. Even people that don’t have a lot of money here are willing to give what they can to help others who have less or are in some need. We’ve found as we grow the engagement of people with our work, our giving goes up.”

In general, the highest share of income is donated in Utah and in the South. The least charitable states were New Hampshire, Maine and Vermont. The Chronicle report, that looked at IRS returns, found that Americans who earn $200,000 or more actually reduced their giving by 4.6% from 2006 to 2012. Those earning less than $100,000, however, increased their charitable giving by 4.5% in the same period.