WDAC has consistently ranked within the top 3-4 stations in the Lancaster ratings -- usually with WIOV, WLAN, and WQXA. In fact, a few years ago they actually came in #1 for Lancaster for one or two ratings books, and they promoted it on some billboards throughout the county. It also consistently comes between #10-15 for Harrisburg and maybe a little lower for York.
I don't know about the revenue, but the station is privately owned by Paul Hollinger (retired station manager) and two sons of the founder. The station has been on the air since 1959 with virtually the same format, and it consistently receives strong support from both its listeners and advertisers.
Another thing of interest is that, according to the station's web site, all of the weekday air personalities have 25+ years worth of experience with WDAC. They even have two sales reps who started with the station 45 years ago in 1963. That is something quite rare these days.