-74.42% is the change from 391 to 100
Calculation steps:
[( 100 - 391 ) ÷ 391] x 100 = -74.42%
Formula
Percentage change = [(100 - 391) / 391] x 100
Subtract the new number by the original number
100 - 391 = -291
-291 ÷ 391 = -0.7442455242966752
-0.7442455242966752 x 100 = -74.42%