MasTec Stock Slides 21% Over 11 Straight Down Days
Shares of MasTec (MTZ) have closed lower in each of the last 11 sessions, a cumulative decline of 20.7%. That erased about $3.7 billion from the company’s market value, which now stands at about $14.1 billion. The stock closed at $180.96 on Wednesday, October 21, its lowest close of the past year.

How The Streak Stacks Up Against The S&P 500
Returns for MTZ and the S&P 500 over the streak and the periods around it, all ending Wednesday, October 21 and including dividends:
| Return Period | MTZ | S&P 500 |
|---|---|---|
| 1 Day | -3.4% | 0.6% |
| 11 Days (Current Streak) | -20.7% | -0.8% |
| 1 Month (21 Trading Days) | -18.4% | 0.0% |
| 3 Months (63 Trading Days) | -49.6% | 5.0% |
| Year To Date | -16.8% | 14.4% |
| 1 Year (252 Trading Days) | -11.8% | 16.5% |
Is This Move About MasTec Or The Market?
Over the same 11 trading days, the S&P 500 returned -0.8% including dividends, so the slide is mostly MasTec’s own story rather than the market’s. Over the past three months the stock is down 49.6%, a window that includes the streak; over the other 52 sessions of that window it was down 36.4%.
Do The Fundamentals Justify The Selling?
On the fundamentals, revenue grew 23.5% over the last twelve months, against a median of 7.6% for S&P 500 Industrials stocks; its operating margin is 5.1%, versus a median of 17.6%; and the stock trades at 28.6 times trailing earnings against a median of 26.6. The read is mixed: revenue growth above the median on one side, margins below the median on the other.
A slide like this raises an obvious follow-up: which marked-down stocks are actually worth buying? Our Buy the Dip screen runs that test every day, flagging beaten-down names whose fundamentals still hold up.
Falling Prices Test Conviction. Rules Do Not Flinch
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