Seventy years ago today, Billboard published its first chart ranking the sales of recorded songs.

In the July 27, 1940, issue, the maiden 10-position "National List of Best Selling Retail Records" paved the way for seven decades - and counting - of Billboard's hallmark tracking of music popularity.

Subsequently, the Country Songs chart, then-titled "Most Played Juke Box Folk Records," would begin highlighting the biggest country recordings in the Billboard issue dated Jan. 8, 1944. The Billboard 200 would begin showcasing the top-selling weekly albums as of March 24, 1956. The premise introduced on this date 70 years ago of ranking the best-selling songs in the U.S. would expand to include a radio airplay component, spurring the birth of the Billboard Hot 100 as the premier national singles chart in the Aug. 4, 1958, issue. Billboard's fourth-most senior active survey, Adult Contemporary, launched July 17, 1961.

Prior to July 27, 1940, Billboard had highlighted the national "Sheet Music Best Sellers"; "Records Most Popular on Music Machines" (compiled from national reports from phonograph operators); and, "Songs With the Most Radio Plugs" on a handful of New York radio stations.

The "National List of Best Selling Retail Records," however, was the first to poll retailers nationwide on record sales.

The new chart was billed as a "trade service feature," based on the "10 best selling records of the past week" at a selection of national retailers from New York to Los Angeles. In addition to stores specifying in recordings, the potpourri of contributors included Sears, Roebuck & Co. in Chicago, J.B. Branford Piano Co. in Milwaukee and Nolen's Radio Service Shop in Birmingham, Ala.

Tommy Dorsey crowned the inaugural retail list with "I'll Never Smile Again." The eventual standard, featuring vocals by Frank Sinatra, would total 12 weeks at the summit. Not only did Dorsey top the first Billboard singles sales chart, but the bandleader also placed at No. 8; his older brother Jimmy ranked at No. 2. Glenn Miller claimed three of the first tally's top 10.

Here is a look at the introductory Billboard songs chart dated 70 years ago today:

Position, Title, Artist
No. 1, "I'll Never Smile Again," Tommy Dorsey

No. 2, "The Breeze and I," Jimmy Dorsey
No. 3, "Imagination," Glenn Miller
No. 4, "Playmates," Kay Kyser
No. 5, "Fools Rush In," Glenn Miller
No. 6, "Where Was I?," Charlie Barnet
No. 7, "Pennsylvania 6-5000," Glenn Miller
No. 8, "Imagination," Tommy Dorsey
No. 9, "Sierra Sue," Bing Crosby
No. 10, "Make Believe Island," Mitchell Ayres