-67.67% is the change from 665 to 215
Calculation steps:
[( 215 - 665 ) ÷ 665] x 100 = -67.67%
Formula
Percentage change = [(215 - 665) / 665] x 100
Subtract the new number by the original number
215 - 665 = -450
-450 ÷ 665 = -0.6766917293233082
-0.6766917293233082 x 100 = -67.67%