(Harrisburg) -- More than 1.8 million Pennsylvanians will be affected by reductions to food stamp benefits that take effect today, as federal stimulus funding, which has been boosting the Supplemental Nutrition Assistance Program (SNAP) since 2009, expires.

The benefits are being reduced by more than five percent across-the-board.

Laura Tobin Goddard, executive director of the Pennsylvania Hunger Action Center, says the loss affects families who can least afford it.

"For an average family of four, it's going to be equivalent to taking away 21 meals a month, so it's pretty significant," she says. "For a household of four it's a reduction of $36 in their monthly benefit."

Pennsylvania's average monthly SNAP benefit was about $265 last year, according to the state Department of Public Welfare.

Goddard says the reduction will heap added stress on food banks as families turn to them to fill in the gap.