NEW YORK (MainStreet) — It's time to take a hard look at your 401(k) performance. Does your retirement plan deserve an outperforming, top-of-the class grade 'A' -- or a retirement at-risk failing grade of 'F'? Pull out your third quarter statement and let's see.

According to Fidelity, the average 401(k) balance has risen to a new high value of $84,300 at the end of the third quarter – that's up just over 11% from a year ago. Now remember, that's the average. If you've made about the same return in your retirement plan, your plan investments earn a 'C.'

And for a long-term view of how you're doing, consider this: workers that have been active in their 401(k) plan for the past ten years saw their average balance rise 19.6% to $223,100 over the past 12 months. Age 55 or older pre-retirees that have been in their plan for at least ten years had an average balance of some $269,500 by the end of the third quarter.

Is your plan performance average – or above average?

Whatever the case, it may be due to your investment mix. If you are looking for some help, you might want to consider putting a professional strategy in place. The Fidelity survey finds that one-third of employees now use target-date funds or managed accounts in their retirement plans. Compare that to ten years ago when almost all plan participants slogged through the investment process on their own.

"Today's 401(k) plan is profoundly different than it was a decade ago," says James MacDonald of Fidelity. "Plan design has evolved greatly to reflect the fact that 401(k) plans are often the primary driver of retirement savings for most working Americans. Professionally managed investment options can help working Americans achieve better retirement outcomes by creating a diversified portfolio, which is often the most challenging aspect of participating in a workplace retirement plan."

Target-date funds offer an age-based, diversified portfolio that gradually becomes more conservative as the investor nears retirement. Alternatively, managed accounts can consider a participant's risk appetite, as well as all of an individual's retirement and savings accounts and adjust their 401(k) investments accordingly.

Since the third quarter of 2009, Fidelity says the number of employers offering managed 401(k) accounts to their employees has tripled.

"A managed account acknowledges that some participants prefer a more personalized approach with their investment strategy based on their specific needs, including their emotional tolerance for risk or assets outside their 401(k)," says MacDonald.

--Written by Hal M. Bundrick for MainStreet