Individual retirement account and 401(k) balances increased quarter over quarter in the first half, but fell from the year-earlier period, Fidelity Investments reported Tuesday.

The average 401(k) balance stood at $88,900 at the end of the second quarter, up nearly 2% from the end of the first quarter, but down 2.5% year over year.

The average IRA balance increased slightly from the end of the January-to-March period to $89,700, but was 7% lower than in the 2015 second quarter.

Fidelity based its analysis on 22,000 corporate defined contribution plans and 14.2 million participants, as of June 30. It said these figures included the advisor-sold market, but excluded the tax-exempt market as well as nonqualified defined contribution plans and plans for Fidelity’s own employees.

Fidelity’s IRA analysis was based on 8.2 million IRA accounts.

At the end of the second quarter, a record of some 45% of Fidelity retirement customers had all of their 401(k) assets in target-date funds and managed accounts.

Fidelity said these investors were less likely than others to react to market swings and economic events.

Its analysis showed that among savers with all of their 401(k) savings in a target date fund, only 1% had made an investment change within their account over the past 12 months. This compared with 13% of 401(k) investors with a “do it yourself” approach to retirement savings.

Fidelity’s second-quarter report said the average balance for millennial investors who had been continuously active in their 401(k) plan for 10 years reached a record $92,900, up almost 10% from $84,700 one year ago.

The overall balance for long-term savers reached $241,300 at the end of the second quarter, compared with $231,500 one year ago.

Fidelity reported that more than 400,000 people tapped its online guidance for information on how to increase their savings, establish an emergency fund and details on Social Security benefits, among other topics.

In addition, it said, nearly a quarter of a million people completed the firm’s interactive money checkup, which analyzes an investor’s financial needs and provides guidance.

“Most retirement savers are accustomed to market volatility, but the swings in the second quarter were especially dramatic, including a 600-point drop followed by a nearly 800-point increase,” Doug Fisher, Fidelity’s senior vice president for workplace investing, said in a statement.

“It can be tempting for investors to have a knee-jerk reaction to market volatility, so it’s encouraging that more people are tapping professional guidance to help keep their retirement savings and investing on track.”

Dollar Cost Averaging

Fidelity appended a note to its second-quarter analysis about how stock market declines can sometimes help investors accumulate more in their retirement accounts.

The “dollar cost averaging” investment strategy can help people who contribute the same amount on a regular schedule to their 401(k) or IRA.

When the stock market turns bearish, the price of many investment options can be lower, enabling investors to buy more shares than when prices are high. As a result, declining stock prices can sometimes help individuals increase their retirement savings in the long run when prices eventually rise.

Fidelity cautioned that dollar cost averaging does not ensure a profit or protect against loss in declining markets. For the strategy to be effective, it said, the investors must continue to purchase shares in both up and down markets.

“Millions of our customers are using this approach to save for retirement,” Fisher noted. “When applied to a long-term savings strategy, a lower average cost for the investments in their retirement account may help them accumulate more money for retirement.”

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