-75% is the change from 344 to 86
Calculation steps:
[( 86 - 344 ) ÷ 344] x 100 = -75%
Formula
Percentage change = [(86 - 344) / 344] x 100
Subtract the new number by the original number
86 - 344 = -258
-258 ÷ 344 = -0.75
-0.75 x 100 = -75%
Example