Some people are determined, contributing to their 401(k)s week after week, year after year, whether the market is a happy place or, as it did Thursday, drops 300 points in one go. 

Such persistence, and consistency, don't have to be their own reward, however. In fact, according to a study by the Employee Benefit Research Institute and the Investment Company Institute, workers who kept socking it away in good times and bad — including during the recent financial meltdown — saw their average balances grow at a compound rate of 6.8 percent annually during the five years of the crisis, year-end 2007 to year-end 2012. And that's despite a stomach-churning drop of 34.7 percent in that group's average 401(k) account balance in 2008. 

In case that didn't sink in, there's more.