-84.84% is the change from 521 to 79
Calculation steps:
[( 79 - 521 ) ÷ 521] x 100 = -84.84%
Formula
Percentage change = [(79 - 521) / 521] x 100
Subtract the new number by the original number
79 - 521 = -442
-442 ÷ 521 = -0.8483685220729367
-0.8483685220729367 x 100 = -84.84%