As I mentioned last week, I applied a formula to calculate points earned by songs that hit AT40 over the 1981 chart year, and then used it come up with predictions for what Casey would count down on the weekends of 1/26/81 and 1/2/82. It was analogous to what I’d done for my own charts: here it was (41 – n) points, where n was the song’s position, plus 10 extra points for each week on the show, with bonuses for multiple weeks at #1 (so a week at #30 got 11 + 10 = 21, a week at #8 got 33 + 10 = 43, etc.). Here’s a sample of the painstaking labor involved:
The end result came out thusly:
Ah, but what did I use as the chart year? I’d remembered that back in 1976, Casey had said they used first week of November to last week of October, so I assumed that five years on that was still the case. This list is based on a 11/1/80-10/31/81 chart year. How did I do? Here’s the full countdown–the three numbers next to each song are: 1) # of weeks on the chart during my theorized chart year; 2) peak position in said chart year; 3) my prediction.
I think you can make a strong case that the 10-points-per-week-on-AT40 was a decent proxy for what the folks creating this list actually did, awarding (101-n) points for every week on the Hot 100 (along with bonuses for weeks at #1). There are several clumps of songs (#96-#90, #82-#78, #76-#71, for instance) that were grouped together in my predictions, albeit I had placed each group several positions higher on the countdown. My big failure was in not realizing that they were going to extend the chart year well into November of 1981, either two or three weeks (two weeks would get “Hard to Say” and “I’ve Done Everything for You” in about the right spots, but even three more weeks isn’t enough to explain the big misses on “Tryin’ to Live My Life Without You,” “Start Me Up,” “Arthur’s Theme,” and especially “Private Eyes”). It appears they also bestowed credit for some weeks in October of 1980, based on my low-balling of “Dreaming,” “Whip It,” “The Wanderer,” and “Lady,” among others. Alas, I just wasn’t going to get it right, but the effort was certainly fun.