100% is the change from 270 to 540
Calculation steps:
[( 540 - 270 ) ÷ 270] x 100 = 100%
Formula
Percentage change = [(540 - 270) / 270] x 100
Subtract the new number by the original number
540 - 270 = 270
270 ÷ 270 = 1
1 x 100 = 100%
Example