Why Is MasTec ( $MTZ ) Stock Down -7.30% Today? (Find out why any stock moved today on Tickeron.) MasTec (MTZ) shares fell roughly 7.30% in intraday trading, sliding to about $209.16 from a prior close of $225.62. The decline extended a multi-week sell-off rather than reacting to a single fresh headline, reflecting lingering fallout from the company's second-quarter earnings report. $PWR $FIX $MYRG $EME $IESC