-3.71% is the change from 512 to 493
Calculation steps:
[( 493 - 512 ) ÷ 512] x 100 = -3.71%
Formula
Percentage change = [(493 - 512) / 512] x 100
Subtract the new number by the original number
493 - 512 = -19
-19 ÷ 512 = -0.037109375
-0.037109375 x 100 = -3.71%