Pension fund revenues, as measured by investment returns and contributions, were notably higher between 2010 and 2015 relative to the 24 years prior. Increases have been driven primarily by investment gains, which, while more volatile, have added more to plan assets than in the 2000s, even when excluding 2009.

Employee and employer contributions have been less additive, albeit less volatile, adding an average of 6% and 10%, respectively, to plan assets since 2010.