Flash back to March 9, 2009. The U.S. economy was just beginning to emerge from the Great Recession that had dragged down the stock market. For instance, the Dow industrials fell from 14,093 in October 2007 to 6,547 on March 9, 2009.

The freefall caused many investors to swear off stocks because they were just too "risky." Turns out the decline actually created one of the greatest buying opportunities in stock market history, with the DJIA and other market indexes tripling in value in the next eight years.

Has it been a straight line up? Heck no. there have been a few corrections - a decline of 10 percent or more - and numerous dips of around five percent. Each time there was a hiccup in the markets you could hear scared investors say "Here we go again!" Nothing was further from the truth. In fact, any dipped proved to be a new buying opportunity.

To be sure, there are plenty of permanent bears out there, constantly calling for a massive drop in stock prices. And, of course, it could actually occur. Unfortunately no one knows when or why it will occur. Investors who have stayed the course over the last eight years are the winners, not whiners.  

Wall Street