These are the number-one hits on the Top 100 Singles chart in 1979 as published by Cash Box magazine. +KeyIndicates best-performing single of 1979
Issue date Song Artist January 6 "Le Freak" Chic January 13 January 20 January 27 February 3 "Da Ya Think I'm Sexy?" Rod Stewart February 10 February 17 February 24 March 3 March 10 "I Will Survive" Gloria Gaynor March 17 "Tragedy" Bee Gees March 24 March 31 April 7 "What a Fool Believes" Doobie Brothers April 14 April 21 "Knock on Wood" Amii Stewart April 28 "Heart of Glass" Blondie May 5 "Reunited" Peaches & Herb May 12 May 19 May 26 June 2 "Hot Stuff" Donna Summer June 9 June 16 June 23 June 30 "Ring My Bell" Anita Ward July 7 July 14 July 21 "Bad Girls" Donna Summer July 28 August 4 August 11 "Good Times" Chic August 18 "My Sharona" The Knack August 25 September 1 September 8 September 15 September 22 September 29 "Sad Eyes" Robert John October 6 October 13 "Don't Stop 'til You Get Enough" Michael Jackson October 20 "Sail On" Commodores October 27 "Rise" Herb Alpert November 3 November 10 "Heartache Tonight" Eagles November 17 "Still" Commodores November 24 "Babe" Styx December 1 December 8 December 15 "No More Tears (Enough Is Enough)" Barbra Streisand & Donna Summer December 22 "Escape (The Pina Colada Song)" Rupert Holmes December 29
See also 1979 in music List of Hot 100 number-one singles of 1979 (U.S.)
References http://cashboxmagazine.com/archives/70s_files/1979.html