Divide two measures, but gives wrong answer when I represent it as percentage

Hello all, 

I'm trying to divide two measures I have created in power bi, and in gives a correct answer.

But when I display the answer in percentage in gives a wrong answer.

This is my measure,

CO2 Ratio = DIVIDE(([1st Period CO2 from energy] - [2nd Period CO2 from energy]),[1st Period CO2 from energy])

It gives as example 15.54%, and the correct answer is 15.11%.

Can someone help me to fix the issue?

Thank you