So what? The Dow is a terrible indicator of even how well the stock market or the economy as a whole is doing. It is price weighted instead of market cap weighted so smaller companies that released fewer shares at a higher price have more impact on the Dow than larger companies. http://www.npr.org/sections/money/2017/01/04/508261371/episo...
It's still important for the Dow Theorists (if there are any left).
"Trends persist until a clear reversal occurs."
In other words, if you find yourself falling, you're no longer rising.
Useful.