construction of cvn-79 john f . kennedy , construction of the u.s . coast guard 2019s fifth national security cutter ( unnamed ) , advance planning efforts for the cvn-72 uss abraham lincoln rcoh , and continued execution of the cvn-71 uss theodore roosevelt rcoh . 2010 2014the value of new contract awards during the year ended december 31 , 2010 , was approximately $ 3.6 billion . significant new awards during this period included $ 480 million for the construction of the u.s . coast guard 2019s fourth national security cutter hamilton , $ 480 million for design and long-lead material procurement activities for the cvn-79 john f . kennedy aircraft carrier , $ 377 million for cvn-78 gerald r . ford , $ 224 million for lha-7 ( unnamed ) , $ 184 million for lpd-26 john p . murtha , $ 114 million for ddg-114 ralph johnson and $ 62 million for long-lead material procurement activities for lpd-27 ( unnamed ) . liquidity and capital resources we endeavor to ensure the most efficient conversion of operating results into cash for deployment in operating our businesses and maximizing stockholder value . we use various financial measures to assist in capital deployment decision making , including net cash provided by operating activities and free cash flow . we believe these measures are useful to investors in assessing our financial performance . the table below summarizes key components of cash flow provided by ( used in ) operating activities: .

year ended december 31 2011: net earnings ( loss ): -94
goodwill impairment: 290
deferred income taxes: 27
depreciation and amortization: 190
stock-based compensation: 42
retiree benefit funding less than ( in excess of ) expense: 122
trade working capital decrease ( increase ): -49
net cash provided by ( used in ) operating activities: 528
year ended december 31 2010: net earnings ( loss ): 135
goodwill impairment: 0
deferred income taxes: -19
depreciation and amortization: 183
stock-based compensation: 0
retiree benefit funding less than ( in excess of ) expense: 33
trade working capital decrease ( increase ): 27
net cash provided by ( used in ) operating activities: 359
year ended december 31 2009: net earnings ( loss ): 124
goodwill impairment: 0
deferred income taxes: -98
depreciation and amortization: 186
stock-based compensation: 0
retiree benefit funding less than ( in excess of ) expense: -28
trade working capital decrease ( increase ): -272
net cash provided by ( used in ) operating activities: -88

cash flows we discuss below our major operating , investing and financing activities for each of the three years in the period ended december 31 , 2011 , as classified on our consolidated statements of cash flows . operating activities 2011 2014cash provided by operating activities was $ 528 million in 2011 compared with $ 359 million in 2010 . the increase of $ 169 million was due principally to increased earnings net of impairment charges and lower pension contributions , offset by an increase in trade working capital . net cash paid by northrop grumman on our behalf for u.s . federal income tax obligations was $ 53 million . we expect cash generated from operations for 2012 to be sufficient to service debt , meet contract obligations , and finance capital expenditures . although 2012 cash from operations is expected to be sufficient to service these obligations , we may from time to time borrow funds under our credit facility to accommodate timing differences in cash flows . 2010 2014net cash provided by operating activities was $ 359 million in 2010 compared with cash used of $ 88 million in 2009 . the change of $ 447 million was due principally to a decrease in discretionary pension contributions of $ 97 million , a decrease in trade working capital of $ 299 million , and a decrease in deferred income taxes of $ 79 million . in 2009 , trade working capital balances included the unfavorable impact of delayed customer billings associated with the negative performance adjustments on the lpd-22 through lpd-25 contract due to projected cost increases at completion . see note 7 : contract charges in item 8 . the change in deferred taxes was due principally to the timing of contract related deductions . u.s . federal income tax payments made by northrop grumman on our behalf were $ 89 million in 2010. .

Questions:
what is the net cash flow by operating activities in 2010?
what about in 2009?
what is the difference among these years?
what is the net cash flow by operating activities in 2099?
what percentage change does this represent?

Answers:
359
-88
447
88
507%