The percentage of their income Plymouth residents give to charity is less than the county, state and country averages, according to a study released Monday.

However, those making the least amount of money in Marlborough give the most, percentage-wise.

The Chronicle of Philanthropy's "How America Gives" study reported that Plymouth residents, with a median discretionary income of $55,968, had a median contribution of 2.2 percent, or $1,200, of their income to charity in 2008, the tax year for which data was collected.

By way of comparison, the county, state, and country's median contribution was 3.2 percent, 2.8 percent and 4.7 percent, respectively. (See chart below.)

The study is based on exact dollar amounts released by the Internal Revenue Service that show the value of charitable deductions claimed by American taxpayers in 2008. 

The Chronicle’s rankings show the percentage of their income that households donated from the money they had left after paying their taxes and covering housing, food, and other essential expenses.

Detailed data is searchable by zip code.

While The Chronicle used averages to compare towns, readers may also search by income bracket. The study shows that those making the least money in Plymouth donated the largest percentage of their income. The tax returns reporting median discretionary income of $10,000 to $70,999 in Plymouth gave an average of 2.8 percent of their income, or $955. That is the average of 5,423 tax returns and an average income of $33,667. 

Those making $70,000-$199,999 reportedly gave 2 percent and those more than $200,000 also gave 2 percent.