The reason it needs to be spelled out is for clarification. Sometimes, depending on the font used, time passing and eroding the paper, scanning, etc, the numbers become difficult to read. a 8 can look like a 3 a 7 like a 1, etc. This is why it is required that on Legal Documents which includes numbers also be spelled out. I came upon this site because I too work in the legal field and need help with how to spell out 2.04 percent. I think it is two and four one-hundredths percent, but wanted to be sure. Any body out there have an answer?