I'd go further. 1978 was, arguably, the greatest year in the history of pop. It had everything - new wave's commercial peak (Denis Denis, Rat Trap, Rhythm stick climbing at the end of the year), disco's peak (Night Fever, Le Freak), all time classics (Baker Street, Wuthering Heights) and some of the biggest selling singles of all time. Just the argument to put at any management meeting that was thinking of stopping these re-runs!
78 was good but 79 was even better, all the genre's you quote but also the real arrival of mainstream electronic music in the guise of Gary Numan/Tubeway Army.
Has there ever been a more varied selection of Number Ones?
Village People - Y.M.C.A.
Ian And The Blockheads - Hit Me With Your Rhythm Stick
Blondie - Heart Of Glass
Bee Gees - Tragedy
Gloria Gaynor - I Will Survive
Art Garfunkel - Bright Eyes
Blondie - Sunday Girl
Anita Ward - Ring My Bell
Tubeway Army - Are 'Friends' Electric?
Boomtown Rats - I Don't Like Mondays
Cliff Richard - We Don't Talk Anymore
Police - Message In A Bottle
Buggles Video Killed The Radio Star
Lena Martell - One Day At A Time
Dr.Hook - When You're In Love With A Beautiful Woman
Police - Walking On The Moon
Pink Floyd - Another Brick In The Wall (Part II)