-98.7% is the change from 998 to 13
Calculation steps:
[( 13 - 998 ) ÷ 998] x 100 = -98.7%
Formula
Percentage change = [(13 - 998) / 998] x 100
Subtract the new number by the original number
13 - 998 = -985
-985 ÷ 998 = -0.9869739478957916
-0.9869739478957916 x 100 = -98.7%