Balance sheet
	2010	2011			2010	2011
Cash	4,600	3,800		Accounts payable	16,200	17,100
Accounts receivable	10,200	9,700		Long-term debt	36,000	33,400
Inventory	18,900	20,300		Common stock	14,000	20,000
Net fixed asset	41,400	42,100		Retained earning	8,900	5,400
Total asset	75,100	75,900		Total claim	75,100	75,900

Income statement 2011
Net sales	61,600
Cost	48,900
Depreciation	7,800
EBIT	4,900
Interest	2,500
EBT	2,400
Taxes	800
Net income	1,600

What is the amount of the change in net working capital using the above financial statements ?