-49.5% is the change from 400 to 202
Calculation steps:
[( 202 - 400 ) ÷ 400] x 100 = -49.5%
Formula
Percentage change = [(202 - 400) / 400] x 100
Subtract the new number by the original number
202 - 400 = -198
-198 ÷ 400 = -0.495
-0.495 x 100 = -49.5%