It's a Busy Day at the Dog Track

Stocks plunged at the open, triggering a freeze on trading, as "Circuit Breakers" shut down trading for the first time in 23 years.

The issue here is not risk, that is possibility quantifiable possibility of something bad happening, but uncertainty, where your numbers go ¯\_(ツ)_/¯ :

U.S. stocks careened lower Monday, with major indexes swinging perilously close to the first bear market in more than a decade as a price war for oil and fallout from the coronavirus frightened investors.

The selling was heavy across markets and geographies, with investors seeking shelter in government bonds, sending Treasury yields to new lows. U.S. stocks fell hard enough at the open to trigger a circuit breaker for the first time in 23 years that kept trading frozen for 15 minutes. The Dow Jones Industrial Average suffered its worst decline since 2008 and at one point came within 65 points of touching a bear market.

For the day, the Dow sank 2,013.76 points, or 7.8%, to 23851.02. It was the first time the Dow lost more than 2,000 points in a session. The S&P 500 fell 225.81 points, or 7.6%, to 2746.56, also its worst day since 2008. And the Nasdaq Composite slid 624.94 points, or 7.3%, to 7950.68.

All 11 sectors in the S&P 500 were down, led by energy, which slid 20%. Financials were down 11%. Industrials and materials both fell 9.2%.

By day’s end, the Dow, S&P and Nasdaq were all down roughly 19% from record highs set earlier this year. A drop of 20% from those highs would halt a bull-market run that began after the financial crisis. Stocks bottomed out 11 years ago, on March 9, 2009.

As an aside, this is the time when I DON'T look at how my IRA or 401(k) is doing, 

Seriously, just don't.