33.59% is the change from 512 to 684
Calculation steps:
[( 684 - 512 ) ÷ 512] x 100 = 33.59%
Formula
Percentage change = [(684 - 512) / 512] x 100
Subtract the new number by the original number
684 - 512 = 172
172 ÷ 512 = 0.3359375
0.3359375 x 100 = 33.59%