It is believed that the 25-year-old singer's team looked into how much her legs were worth in case anything happens while she is on stage, reported Grazia magazine.
"It seems like a ludicrous sum, but if something was to happen to her legs, Swift wouldn't be able to give her signature stage performances. Her USD 200 million career would be in big trouble, "a source said.
The Blank Space singer was said to be "embarrassed" when she found out how much her legs were worth.
"She thought her legs were possibly worth a million. But USD 40 million shocked her. She's even a little embarrassed about it" the source said.