I need help with my finance, computing the payback period statistic. Here is the problem:

6.) Compute the payback period statistic for the table and recommend whether the firm should accept or reject the project with the cash flows shown in the chart if the maximum allowable payback is four years

Time	0	1	2	3	4	5
Cash Flow	-$1,000	$350	$480	$520	$300	$100