In a new skit for comedy video website Funny Or Die, Ke$ha has revealed the reasoning behind the dollar sign in her name.

In the mockumentary, entitled ‘The Story of the $’, Ke$ha explains that the letter replacement came about when the star had a birthday party at a Shakey’s Pizza franchise.

"I used to be Kesha with an S, instead of a dollar sign, and then one year I had my birthday party at Shakey's Pizza," she says in a mock sombre voice."On the sign, the big sign where they write 'Happy birthday,' they replaced the S with a dollar sign."

The skit then introduces a character named Joe Trundle, an employee at the pizza place, who says they were out of S letters for the sign that day.

Ke$ha continues dramatically: "It ruined my life. I wanted to be a CPA, but you know who H&R Block doesn't hire people with dollar signs in their name. I pretty much had to be a pop star."

Watch the new Funny Or Die skit below: