In connection with our initial public offering in September 1995, our shareholders authorized our Management Board to repurchase  up to 10% of our issued share capital, the maximum allowed under Dutch law at the time, for a period of 18 months. This authoriza- tion was renewed at subsequent annual or special shareholder meetings. At our annual shareholders’ meeting on May 16, 2013, our  shareholders authorized an extension until November 16, 2014 to purchase up to 10% of our issued share capital which may be used for any legal purpose. The repurchase of shares in the open market is at the discretion of management pursuant to this shareholder authorization. From the activation of the share repurchase program through December 31, 2013, we have repurchased 36,186,389 shares for an  aggregate purchase price of approximately $1.2 billion, or an average price of $32.91 per share. At December 31, 2013, we held  1,648,613 shares in treasury and have the authority to repurchase 3,026,387 additional shares under our stock repurchase program  as described in the preceding paragraph. The selected consolidated financial information contained below is derived from our Consolidated Financial Statements and should be  read in conjunction with “Item 7. Management’s Discussion and Analysis of Financial Condition and Results of Operations” and our  audited Consolidated Financial Statements each of which is included in this Form 10-K. ITEM 6. SELECTED FINANCIAL DATA (1)  Current ratio is calculated as follows: current assets divided by current liabilities. (2)  Debt to EBITDA ratio is calculated as follows: debt divided by the sum of net income plus interest, taxes, depreciation and amortization. For the Years Ended December 31, (in thousands, except per share and other data) 2013 2012 2011 2010 2009 Financial Statement Data: Revenue $ 1,073,508 $ 981,080 $ 907,648 $ 794,653 $ 695,539 Net income attributable to Core Laboratories N.V. 242,811 216,071 184,684 144,917 113,604 Working capital 168,093 156,397 143,353 69,967 284,129 Total assets 661,010 636,516 610,873 650,241 658,166 Long-term debt and capital lease obligations, including current maturities 267,028 234,073 225,419 147,543 209,112 Total equity 169,389 187,913 181,655 292,340 281,758 Earnings Per Share Information: Net income attributable to Core Laboratories N.V.: Basic $ 5.31 $ 4.58 $ 3.99 $ 3.23 $ 2.47 Diluted $ 5.28 $ 4.54 $ 3.82 $ 3.00 $ 2.43 Weighted average common shares  outstanding: Basic 45,692 47,211 46,286 44,830 45,939 Diluted 45,994 47,553 48,393 48,241 46,657 Cash dividends declared per common share $ 1.28 $ 1.12 $ 1.00 $ 0.890 $ 0.575 Other Data: Current ratio (1)  2.24:1 2.11:1 2.00:1 1.25:1 3.67:1 Debt to EBITDA ratio (2)  0.74:1 0.73:1 0.83:1 0.59:1 0.99:1 16