AT40 and "top selling singles"

Hope this isn't off topic -- since we talk a lot about American Top 40 here, I suspect someone has an answer to this.

Listening to old AT40s, at least in the early '70s, the show claims to play the 40 top-selling singles, but the show uses the Hot 100, which incorporates both sales and airplay data.

By chance, I found similarly curious claims in a Billboard story from 1970. The writer says AT40 would play the top 40 from the Hot 100, but he also called these songs the "major-selling 40."

Can anyone reconcile these claims? Was the Hot 100 so heavily weighted to sales that "top selling singles" was reasonable shorthand?


Billboard story from May 1970

Brian W. wrote: What page is the story on, Eric?

It starts in the middle of page 1, and there's a hyperlink jump to the conclusion.   

Clearly from that last statement, they use the term "best selling" to mean based on "retail sales and radio station airplay". So it's probably always been a combo of the 2. As for the weight of airplay vs. sales, I believe this has changed from time to time, certainly in the '80s and '90s.

The Hot 100 has always been a combination of sales and airplay. It's my understanding that the actual percentages have varied over the years. Here's an actual sentence from Billboard's issue dated August 4, 1958, the introduction of the very first Hot 100 chart:

Weighted factors in the carefully designed formula include disk jockey plays, juke box activity and sales at the retail level.

Hykker wrote: Even in the 90s, when we reported weekly spins to the trades it was honor system. We called the trade papers & told them how many spins per title from the past week. Easy to fudge if we'd wanted to. For that matter, sales figures were pretty suspect and subject to manipulation before Soundscan.

Absolutely. I have a relative who is a former radio DJ and program director for a classic rock station that reported to Billboard. He laughed when he told me that they used to just write whatever the hell they wanted on their reporting lists.

I remember reading a Billboard article where one of their chart people, might have been Geoff Mayfield, said how shocked they were when they began doing the unpublished test charts with SoundScan. They were amazed at how far off the actual figures were from what the radio stations and record stores were reporting.

While the Hot 100 continued to be compiled from those airplay/sales reports for the first several months, the Hot 100 Singles Sales and Hot 100 Airplay charts, as published, were taken from SoundScan, so we can see just what the difference was during that time.

One example that comes to mind is Rod Stewart's "The Motown Song." It hit #10 on the Hot 100 pre-SoundScan system. But the Sounscan-based sales and airplay breakdown shows it peaked at #24 airplay and #36 sales. That song would NEVER have been top ten if Billboard had begun compiling the Hot 100 from SoundScan earlier.

The George Michael/Elton John duet of "Don't Let the Sun Go Down On Me" would likely never have hit #1 on the Hot 100, either... I think it peaked at #4 in both sales and airplay. And "I Wanna Sex You Up" probably would have been a #1 hit.