-98.63% is the change from 512 to 7
Calculation steps:
[( 7 - 512 ) ÷ 512] x 100 = -98.63%
Formula
Percentage change = [(7 - 512) / 512] x 100
Subtract the new number by the original number
7 - 512 = -505
-505 ÷ 512 = -0.986328125
-0.986328125 x 100 = -98.63%