While I'm not certain when WRAL-FM halved their power, I'll venture a guess it was in, or no later than, 1978 when the 2,000-foot WRAL-TV tower was completed, replacing the adjacent, shorter (I believe 1,500-foot) structure TV-5 had used since its 1956 sign-on. WRAL-FM was side-mounted at the 1,840-foot level of the new tower with a 100,000-watt signal.
In 1989, uneven thawing of that December's ice storm brought the WRAL tower down, along with another that supported then-NBC affiliate WPTF-TV 28. WRAL-FM temporarily moved to the old WPTF-TV tower in Apex (which now stands in Rolesville as the WCPE-FM tower) while WRAL and the former WPTF-TV (now WRDC) completed a joint 2,000-foot tower. WRAL-FM's antenna at the new, joint WRAL/WPTF-TV tower was mounted at, I think 1,868 feet. However high it is now, it was high enough to constitute a slight drop in power to the current 96,000 watts. TV 28's then-sister FM station, WQDR 94.7, dropped their power from 100,000 watts to 96,000 watts as well when they moved from Apex (they never operated from TV 28's old tower in Garner for some reason) to a higher perch on the new joint tower.