First recorded by The Carpenters (JPN #21 1972).
First hit version by Lynn Anderson (C&W #2 1973).
Other hit version by The Carpenters (US #1/UK #5/CAN #1/IRE #3 1973).
From the wiki: “‘Top of the World’ is a 1972 song by The Carpenter originally recorded for and released on the duo’s 1972 studio album A Song for You. Co-written by Richard Carpenter with lyricist John Bettis (‘Human Nature’, ‘Slow Hand’), ‘Top of the World’ was intended to be only an album cut for the Carpenters. The original album recording was released as a single in Japan in 1972, where it peaked at #21 on the Orion music chart. Soon after its album release, Country singer Lynn Anderson covered the song and was the first to release it as a US single.
“Anderson’s version nearly topped the Country Singles chart, reaching #2. Karen Carpenter, then, not quite satisfied with the original, re-recorded the song for The Carpenter’s first compilation album. It was this recording that topped the Billboard Hot 100 and the Canadian Singles chart, and was also a Top 5 hit in the UK and Ireland.”
Lynn Anderson, “Top of the World” (1973):
The Carpenters, “Top of the World” re-recording (1973):