some quick math... 15.3 over 6 years, about 2.5b/yr, off of $426 invested... just a bit over 0.5% ROI. Meanwhile in late 2008, 10 yr notes were yielding about 2.6%. So the "profit" was about 80% less than the risk-free rate.

https://www.clevelandfed.org/en/our-research/indicators-and-...