On the income statement, why has the Basic Earnings per share have changed dramatically between 2016 and 2018?

Comcast Corporation Consolidated Statement of Income 2018 2017 2016 Year ended December 31 (in millions, except per share data) Revenue S 94,507 $ 85,029 $ 80,736 Costs and Expenses: Programming and production 29,692 25,355 24,348 Other operating and administrative 28,094 25,449 23,840 Advertising, marketing and promotion 7,036 6,519 6,291 Depreciation 8,281 7,914 7,464 Amortization 2,736 2,216 1,962 Other operating gains (341) (442) Total costs and expenses 75,498 67,011 63,905 Operating income 19,009 16,831 (3,542) Interest expense Investment and other income (loss), net 18,018 (3,086) 421 (2,942) 437 (225) Income before income taxes 15,242 15,353 14,326 Income tax (expense) benefit (3,380) 7,569 (5,298) Net income 11,862 22,922 9,028 Less: Net income attributable to noncontrolling interests and redeemable subsidiary preferred stock Net income attributable to Comcast Corporation 131 187 350 $ 11,731 $ 22,735 $ 8,678 2.56 $ 4.83 $ 1.80 Basic earnings per common share attributable to Comcast Corporation shareholders Diluted earnings per common share attributable to Comcast Corporation shareholders 2.53 $ 4.75 0.63 $ $ 1.78 0.55 Dividends declared per common share $ 0.76 $