-98.03% is the change from 660 to 13
Calculation steps:
[( 13 - 660 ) ÷ 660] x 100 = -98.03%
Formula
Percentage change = [(13 - 660) / 660] x 100
Subtract the new number by the original number
13 - 660 = -647
-647 ÷ 660 = -0.9803030303030303
-0.9803030303030303 x 100 = -98.03%