In 1999, 4,860 TANF recipients were asked how many hours they worked in the previous week. In 2000, 4,392 of these recipients were again subject to the same TANF rules and were again asked their hours of work during the previous week. The remaining 468 individuals were randomly assigned to a "Negative Income Tax" (NIT) experiment which gave out financial incentives for welfare recipients to work and were subject to its rules. Like the other group, they were asked about their hours of work during the previous week. The data from the experiment are contained in the table below.

What effect did the NIT experiment have on the weekly hours worked of public assistance recipients who worked positive hours during the survey week?Develop a standard difference-in-differences table to support your answer. (Hint: calculate weekly hours worked per working person in 1999 and 2000)

Experiment Table Number of Recipients Total Hours of Work Who Worked at by All Some Time in the Recipients in the Swanr Week EM 15,5?8 20.698 1.1533 2,535 1?,216 23,233 Diff-In-Dl' Model Weekly Hours Worked Per Working Person 1999 2099 Diff Diff-in-Diff