-39.35% is the change from 859 to 521
Calculation steps:
[( 521 - 859 ) ÷ 859] x 100 = -39.35%
Formula
Percentage change = [(521 - 859) / 859] x 100
Subtract the new number by the original number
521 - 859 = -338
-338 ÷ 859 = -0.39348079161816063
-0.39348079161816063 x 100 = -39.35%