2010 10-K: Part II Other Consolidated Financial Data Consolidated Balance Sheet Data 58 As of December 31 ($000)  2006  2007  2008  2009  2010 Cash, cash equivalents, and investments  $ 163,751  $ 258,588  $ 297,577  $ 342,553  $ 365,416 Working capital (1)  70,021  149,490  179,819  236,595  254,556 Total assets (1)  441,207  643,652   803,940  919,083  1,086,302 Deferred revenue (7)  100,525  129,302   130,270  127,114  146,267 Long-term liabilities (1)  10,952  23,166  39,778  45,792  52,153 Total equity (1)  262,792  402,415   530,245  665,789  781,425 ($000) 2006  2007  2008  2009  2010 Consolidated revenue  $ 315,175  $ 435,107  $ 502,457  $ 478,996  $ 555,351 Revenue from acquisitions  (36,434)  (44,226)  (27,125)  (29,590)  (47,850) Unfavorable (favorable) impact of foreign (793)  (3,808)  (1,850)  8,987  (4,362) currency translations  Revenue excluding acquisitions and impact of foreign currency translations (organic revenue) (2)  $ 277,948  $ 387,073  $ 473,482  $ 458,393  $ 503,139 Stock-based compensation expense (3):  Stock options  $  7,169  $  6,475  $  3,710  $  1,002  $  — Restricted stock units  1,406  4,503  7,571  10,591  12,545 Restricted stock  —  —  —  —  1,248 Total stock-based compensation expense  $  8,575  $  10,978  $  11,281  $  11,593  $ 13,793 Cash used for investing activities (4)  $ (129,002)  $ (102,838)  $ (179,124)  $ (174,675)  $ (87,949) Cash provided by financing activities (1) (5)  $  34,415  $  53,796  $ 50,737  $  25,320  $ 12,525 Cash provided by operating activities (1)  $  98,245  $ 111,037  $ 149,339  $ 101,256  $ 123,416 Capital expenditures  (4,722)  (11,346)  (48,519)  (12,372)  (14,771) Free cash flow (1) (6)  $  93,523  $  99,691  $ 100,820  $  88,884  $ 108,645