-19.4% is the change from 665 to 536
Calculation steps:
[( 536 - 665 ) ÷ 665] x 100 = -19.4%
Formula
Percentage change = [(536 - 665) / 665] x 100
Subtract the new number by the original number
536 - 665 = -129
-129 ÷ 665 = -0.19398496240601504
-0.19398496240601504 x 100 = -19.4%