From mid-December through the last day of May 2017, TEGNA shares were placidly trading in the mid-$20 range. Then, on June 1, they fell off a cliff, tumbling to $15.27 per share. At the Closing Bell on Tuesday (6/13), TGNA shares were at $14.65—up 12 cents from yesterday’s close. What ails the company formerly known as Gannett? Zacks Equity Research sought to find the answer.