The stock market fallout of 2008 cost some investors more than half of their portfolios.

Now, a local financial expert says there are indicators to help identify whether you're currently taking too much risk in your portfolio and if your retirement plan is in danger.

While it's a good indicator, as opposed to one-size-fits-all, there's a pretty simple equation to keep in mind when diversifying between stocks and bonds.

"If you take 100 minus your age, typically that's the exposure to the stock market you should have in your portfolio," Kimberly Foss of Empyrion Wealth Management in Roseville said. 

Foss says, for example, if you lost more than you were comfortable with in 2008, it means you have too much exposure to the stock market and should think about reassessing.

"What you want to do, is see how much you're comfortable with, because you've got to stay in the market to be able gain the return when the stock market comes back up again," she said.  

After the market fell 37 percent in 2008, it came back 26 percent the following year.

Those who got out won't get a second chance at the rebound momentum of 2009.