I didn't hear the first show of Casey's Top 40, so I don't know if he mentioned last week's positions or not.
There really wouldn't have been any reason not to, since the chart didn't have any big changes that week or anything.
The next radical change came in the spring of 1994. When R&R debuted their new pop chart, Casey made no mention of it. The show was written very poorly. Almost everything was "survey song #XX this week," however, the debuts and some of the songs moving upward were mentioned.
I remember this chart. I'm sure I've said this in another thread, but I forget which one. Anyway, I tuned in late to the show and found that Casey was playing "Bump 'N Grind", which had been at #12 the week before. I figured that maybe the show started two hours earlier. Then he said the song was #28 and I was like, "Whoa, what happened??" I later noticed he wasn't giving the last week positions, so I figured the chart change I'd heard about through the grapevine had been implemented.
The next chart fluctuation came in the late summer/fall of 2000 when they started using the unpublished Mediabase charts with the whacky recurrent rule. There was no mention of a new chart, but at least he referrenced last week's positions.
I knew something had happened when there were seven debuts on AT20. They had done a chart purge in the process of switching charts.
The next shake-up came about a year later when all three of Casey's shows returned to the R&R charts. Casey mentioned last week's positions in the Top 40 (not sure about Hot AC). On the AC show, which my station was airing at the time, he did mention that there were 2 re-entries from old songs. (A week or two later, another song that had been gone for 6 months also re-entered.)
That was "Back Here" by BBMak, which had been removed via an April chart purge (as were the other two) and was still on the R&R chart. I don't know why they waited a week to bring that back, but whatever. They left on "The Way You Love Me" by Faith Hill (maybe they were making it up to the song for omitting it from their 2000 year-ender).
Sometime in 2003, AT20 (AC) started using a new chart that went by audience impressions and didn't include spins from Delilah's shows (as mentioned in a previous post). But this time, Casey DID point out that they were using a new chart. It wasn't at the top of the show, but later on going into a commercial break. He said that the new chart better reflected what their affiliates were playing, and he ended by saying something like, "...just in case you were wondering."
That was the weekend of February 9, 2003. I knew something seemed weird since there were a few vague chart oddities (several songs that had been doing well falling off - one was "Father And Daughter" by Paul Simon).
In 2005, AT10 (as it was now called), went back to the R&R Top 10. I did hear that first show and Casey did reference last week's positions. Whether they were based on R&R or something else, I don't know.
The last week positions were from the Mediabase chart they were using. Since the differences between the two charts was very small, due to the smaller size, they decided they might as well go back to using the R&R chart.
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