"For some reason"? Let me help you with your short-term memory loss. I posted this about six hours ago:
1988: 3.5 share---tied for 7th with KTNQ.
1989: 2.9 share---#10 station in the market.
1990: 1.9 share---tied for 20th (yes, 20th) with KODJ.
1991: 3.8 share---#6 station in the market.
1992: 4.0 share---#4 station in the market.
No memory loss........I didn't use your stats in that post, because there's no evidence that any particular special(s), in this case, the #1 weekend, cause ratings to slide in '89 and '90. 1989 was the last year of the well-known drumroll jingle, before a newer concept began in 1990. Who knows...