Classic theory could put the market in jeopardy

Transportation stocks have been stuck in reverse. The Dow Jones transportation average has fallen 19 percent in 2015, widely underperforming the Dow and S&P 500, which are down 3 and 2 percent respectively year to date. According to some market participants, the dismal returns could be flashing a warning sign to the overall market. "This [underperformance] really brings in the concern ......