Shares in AMC Networks dropped sharply in early trading Friday following a shaky fourth-quarter earnings report and a conference call with Wall Street analysts. The stock initially drifted down by mid-single-digits in pre-market trading after the earnings release, which revealed a 23% drop in domestic ad revenue and a 16% decline in affiliate revenue. Although it was difficult to draw a direct line between management comments on the call and the stock movement later in the morning, the selloff intensified a ...