How to compile the AT40's top 100 of the year

[corey]

Hi!
In some years AT40 used the Billboard's year-end rankings, but in other years they compiled their own year-end rankings.
I want to know how to compile the AT40's own year-end rankings.

I know Billboard compile their year-end rankings the survey period from December to the following December. And the point of entire chart runs counted even if the songs debuted before the survey period. If the songs still charted the cut-off date, Billboard assumed the point of after the cut-off date and added.
That explains why Chicago's "Look Away" is the number one song of 1989. It only spent two weeks at number one. There were some songs which spent more weeks at number one. Though it spent 24 weeks in the Hot 100, only 16 weeks of them charted during the 1989 survey period. But Billboard counted the whole chart run, it became the top hit of 1989.

I want to know AT40's own year-end chart compiling policy only counts certain 12 months survey period or not. And they added the bonus points to the number one hits or not.

[michaelcasselman]

I was JUST about to start this thread. :-) SO many other threads have been beating around the bush about this subject that it deserved it own thread ( especially this time of the year).

I don't know the exact ins-and-outs of how Billboard *or* AT40 compiled their own EOY charts, but from the time I was a dedicated listener (1984-1993), I did my own running tally with an inverse-point system, based only on top 40 positions (1 pt for #40, 2 for #39, .... 40 pts for #1, frozen weeks counted for the same point values as the week previous to the freeze). Based on the stated cut-off dates (usually Dec-Nov of any given chart year), I went with songs that peaked within that chart year, and 'guesstimated' the projected drop-off of any song that was still in the countdown *at* the end of the calender year. I didn't allow for any extra points for specific positions, and even when I listened to the year-end chart, I was typically off by no more than a couple of positions based on those point values.

(With the aforementioned 'Look Away' example, at the time, I knew even by late-Summer '89 that Chicago was probably going to have the #1 song of the year based on my system, unless some song was going to come along and have an unexpected 10-week #1 streak by Fall of '89.)

[vince]

The way AT40 calculated their year end to 100s varied from year to year. Beginning with 1972 they used the same methodology as BB used at the time. 100 points for #1, 99 points for #2 down to 1 point for #100. 100 bonus points were awarded for each week at #1. This same methodology was used for 1973 and 1977. Records entire chart runs were counted up to a cut off date. The cut off were 11/25/72 for 1972, 12/8/73 for 1973 and 11/12/77 for 1977.

For 1980 they used a similar methodology, but only counted the top 40. 100 Point for #1, 99 points for #2 down to 61 points for #40. No points were given to positions below #40. #1 got 100 bonus points for each week at #1. The entire chart run of songs were counted and songs late in the year such as “Another One Bites The Dust” and “Woman In Love” point totals were estimated.

For 1981, AT40 used an inverse point system that only counted the top 50. It was 50 points for #1, 49 points for #2, down to 1 point for #50. 50 bonus points were awarded for each week at #1. The entire chart run was counted with songs charting late in the year point totals estimated.

1982 to 1984 had the same methodology which is more complicated. First there is an inverse with the top 50, so 50 points for #1, 49 points for #2 down to 1 point for #50. Then top 10 bonus points are added in, 10 points for #1, 9 points for #2, down to 1 point for #10. Additional bonus points are awarded to #1. These can be calculated using the following formula (n*n+3*n)*5, where n = the total number of weeks at #1. 1990 to 1994 supposedly were calculated the same way, but I never checked to see for sure. The frozen weeks were averaged for all years except 1984, where 1/7/84 was counted twice.