-86.07% is the change from 639 to 89
Calculation steps:
[( 89 - 639 ) ÷ 639] x 100 = -86.07%
Formula
Percentage change = [(89 - 639) / 639] x 100
Subtract the new number by the original number
89 - 639 = -550
-550 ÷ 639 = -0.8607198748043818
-0.8607198748043818 x 100 = -86.07%