"All by Myself" is a song by American artist Eric Carmen released in 1975. The verse is based on the second movement (Adagio sostenuto) of Sergei Rachmaninoff's Piano Concerto No. 2 in C minor, Opus 18. The chorus is borrowed from the song "Let's Pretend", which Carmen wrote and recorded with the Raspberries in 1972.

Based on this passage, when did the song all by myself come out? Let's give stream of consciousness first:
To answer this question, we should know that: "All by Myself" is a song by American artist Eric Carmen released in 1975.
So, the final answer is 1975.