Nexen Inc. reported the following selected information for the last five years (in millions, except earnings per share):

Instructions
(a) Calculate Nexen's profit margin, return on assets, and return on common shareholders' equity (for this calculation, note that the company has no preferred shares) before and after discontinued operations for each of the last five years.
(b) Evaluate Nexen's profitability over the last five years before and after discontinued operations.
(c) Which analysis-before or after discontinued operations-is more relevant to investors? Explain.

2012 2011 2010 2009 2008 Net sales Average common shareholders' equity Average total assets Average total assets (excluding 6,430 6,169 5,411 $ 4,203 6,576 8,589 8,0948,218 7,418 6,374 20,302 19,858 22,404 22,528 20,115 discontinued assets held for sale) Profit from continuing operations Profit from discontinued operations Profit Earnings per share from continuing operations Total earnings per share 20,302 19,493 22,030 22,528 20,115 512 1,602 113 536 1,715 3.05 3.26 395 302 697 1,197 0.75 1.32 572 625 0.61 0.61 1.09 2.28 0.98 1.03