Bring in Joel Whitburn. His books on the Billboard charts occupy a lot of space on my bookshelf. His 1999 A Century of Pop Music, which charts all the Top 40 hits from 1900-1999, with an essay before each decade outlying the big events and big musical ones. Just like me, he looks forward to an issue of the Billboard charts. Reading the year end results for 1999 of the Billboard singles charts brought a most disturbing trend to focus.
Record companies are still reluctant to release any sort of single from an album.
No vinyl, CD single. Billboard's charts are a mixture of sales and airplay. But today record companies feel that a commercial single will hinder an album's sales. The results are inconclusive. Billboard says it themselves.