In recent years, Unocal's average return on capital employed has been higher than ChevronTexaco's, 9.4% vs. 8.7%.

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Granted, the return on capital employed on the Phillips 66 side has improved dramatically, from 1% in 2009 to 5% in 2010 to 13% in 2011.

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Return on capital employed: 9.4%.

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Fortunately, recently, professors Nick Bloom, Toby Kretschmer, and John van Reenen (from Stanford, the University of Munich, and the London School of Economics) conducted an extensive study examining the effect of family-friendly practices on hard variables such as firm sales per employee and return on capital employed, using a large database of firms from the US, the UK, Germany, and France.

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Between 1998 and 2001, the aim was to achieve a return on employed capital that was at least equal to its cost (8.5%).

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