I wrote
80son8@siriusxm.com last month about the missing shows. I figured there was nothing to lose.
To recap for this year:
1. L.T.D. "Shine On". I didn't find a listing for this week. Held the #40 position for one week. - 1/31/81
2. Yes "Rhythm of Love". I didn't find a listing for this week. Held the #40 position for one week. - 2/6/88
We missed the chance for the two above.
3. Genesis "Man On the Corner". I didn't find a listing for this week. Held the #40 position for two weeks. - 5/8/82, 5/15/82 (second and third week of May)
4. The Cover Girls "Promise Me". I didn't find a listing for this week. Held the #40 position for one week. - 5/21/88 (third week of May)
5. Barbra Streisand "The Way He Makes Me Feel". I didn't find a listing for this week. Held the #40 position for two weeks. - 12/10/83, 12/17/83
These are coming up again in May and December. Hopefully Mark zeroed in on your post.
There were some weeks where a song was at #40 for two or more weeks, but only one week was aired (based on what I could find on forum). This could increase the number of potentially unaired shows. Hopefully all the #40 peaks can air at least once.