I don't understand why so many obsess over the daily ups and downs. DJIA could go up 2000 points this week but be down 5000 points next week. So what? Thirty years from now, it will be up overall and this Chinese virus will be in the history books. Just like the dot.com bust and the 1987 crash is in our history books today.
For myself because long term the market is not entirely rational. PE ratios are ridiculous especially on the NASDAQ and on companies like Netflix. Why Netflix gets a bid say and a boring grocer with a much better balance sheet and PE ratio does not baffles my mind. Imagine if Netflix was a small business. No one would ever buy a business that would take 200 years to pay back the original investment.