A recent Planet Money episode talked about why the Dow Jones Industrial Average is a poor metric of our nation's financial health.  The main point was that you can't compare today's average with the average from 20 years ago without adjusting for inflation, and when you do, today's average isn't that good.  The secondary point was that the DJIA is a group of big companies chosen for secretive reasons and which don't necessarily represent the current state of the economy.  So now every time there's a news headline about the Dow, I ignore it purposefully, instead of just ignoring it because it has absolutely no effect on my life.