33% is the change from 500 to 665
Calculation steps:
[( 665 - 500 ) ÷ 500] x 100 = 33%
Formula
Percentage change = [(665 - 500) / 500] x 100
Subtract the new number by the original number
665 - 500 = 165
165 ÷ 500 = 0.33
0.33 x 100 = 33%
Example