“‘Party in the U.S.A.’ paid my rent for, like, three years. Actually it was longer than that. That’s where I get most of my money. I write songs. I’m a singer. I love doing endorsements and stuff, but that’s all added on” she says. A lot of artists that under-perform with their own records, make their real money through songwriting royalties. Without calling any names, why do you think some artists make small changes to a song they didn't write originally? It's actually pretty smart, but for the real songwriters, they stay paid.