You have the following information about a project:

Year	1	2	3	4
Revenues	80000	90000	100000	70000
Labor Costs	45000	45000	45000	45000
Raw Material Costs	25000	30000	35000	20000

To implement the project, you need to buy a machine worth $20,000 right now. IRS rules prescribe depreciating the machine over 4 years. At the end of the 4 years, the machine has no salvage value. You must set aside inventory worth $5,000 right now. This inventory increases by 10% every year before it goes to zero at the end of the 4^th year. The opportunity cost of capital is 12% and the relevant tax rate is 30%.

What is the cash flow due to change in working capital at the end of the 4th year?