There are ways you can use the data from FreeERISA to make long-term investment decisions, but what about getting a picture of the larger market?

I advised against looking at 401(k)s to make your own investment decisions because ultimately their successes are up to who holds the plan and even to the allocation decisions of the participants themselves, not to the business-savvy of the plan sponsors. That said, examining the defined contribution and 401(k) world as a whole can be a good barometer of where the economy is headed.

To build my barometer, I took a look at the 10 401(k) plans who had already filed their 2010 form 5500s and had the biggest gains in terms of raw dollars: