The average annual return to cash for the three years since July 2010 has been 0.04%, for example in VMMXX, Vanguard's Prime Money Market Fund, but over that three year period inflation has absolutely raged at 7.18% overall, with the all items CPI soaring to 232.944 from 217.329. With about $10 trillion stuffed away in M2, returns to cash just keeping pace with inflation would have come to $718 billion to savers by now. Instead they've reaped just $4 billion (annually).
In a related note here, the contribution to GDP over the period from the Zero Interest Rate Policy and Quantitative Easing has mirrored the criminal returns to cash:
'But it turns out that the benefits of printing all that new money may have been negligible. According to a new study by two senior US economists, America's second programme of quantitative easing, nicknamed "QE2", boosted economic output by just 0.04pc.'
The rich have gotten richer the old fashioned way: they've stolen it.