How Big a Market Drop Does It Take to Spook Retirement Investors?

"Anxiety around the stock market is normal, but that doesn't mean investors should automatically act on those emotions."

Rowe-Heupler said sticking to one's financial plan or asking a professional for help was a good way to combat fear amid uncertainty. "A financial advisor can be an excellent resource to help keep consumers from making decisions that they may later regret."

The survey results showed that baby boomers had a stronger stomach for a stock market decline than younger investors. 

Thirty-eight percent of boomers said no market decline would prompt them to give up on stocks in their retirement plan, compared with just 18% of Gen Xers and 16% of millennials.

Here's how the different generations responded with regarded to increasing market declines:

• Up to 5%: boomers – 18%; Gen Xers – 19%; millennials – 18%
• Up to 10%: boomers – 23%; Gen Xers – 38%; millennials – 36%
• Up to 20%: boomers – 17%; Gen Xers – 16%; millennials – 19%
• Up to 30%: boomers – 3%; Gen Xers – 10%; millennials – 11%

Survey respondents who identified as Republicans exhibited a higher tolerance for stock market declines than those who identified as Democrats. Twenty-five percent of Republicans but only 19% of Democrats said they would stay in the market whatever the size of a decline.

The results showed that just 13% of parents with children under 18 would keep their retirement funds in stocks no matter how large the decline, compared with about 30% of parents with adult children or no children.

— Related on ThinkAdvisor:

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• Are Your Clients Buckled Up for Market Chaos?