BOSTON (AP) — The nation’s largest administrator of 401(k) plans says account balances grew an average 4 percent in the last quarter. That’s due to a rising stock market, as well as increased contributions from workers and their employers.

Fidelity Investments said on Thursday that the average balance among the 12 million accounts it administers was $75,900 as of the end of September. That’s up from $72,800 at the end of June.