During the 2009 tax year, the average EITC was $2,770 for a family with children and $259 for a family without children. The amount of the credit rises with earned income until it reaches a maximum level and then phases out with higher income.
Workers receive the credit beginning with their first dollar of earned income, which provides more incentive for program participants to work and receive an income, said Ron Haskins, senior fellow with the Brookings Institution.
Haskins said the EITC is "a crucial program because it really helps low income families and makes a bigger impact than almost any other proam we have."
"In my opinion, it's way better than the minimum wage in boosting the income of low income workers," he said. "I'm a Republican and not necessarily a cheerleader for public expenditures, but this is a good one."
Haskins said the estimated 80 percent penetration rate shows the popularity of the program and prevalance among low-income workers.
Families mostly use the EITC to pay for necessities, like repairing homes and commuting for work, said the Center on Budget and Policy Priorities.