Fidelity Investments says the average participant in a 401(k) plan it serves had $74,900 in assets March 31, up 12% from the average balance recorded a year earlier.

The average balance was up 58% from the March 31, 2009, average, according to Fidelity, Boston.

About 10% of the plan participants increased their deferral rate during the first quarter, and the deferral rate increase percentage was the highest Fidelity has found since it began keeping track of that indicator in 1998.

Fidelity has based those figures on an analysis of 16,500 corporate 401(k) plans that use its plan recordkeeping services. The plans have a total of about 11 million participants.

- Allison Bell

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