-78.89% is the change from 431 to 91
Calculation steps:
[( 91 - 431 ) ÷ 431] x 100 = -78.89%
Formula
Percentage change = [(91 - 431) / 431] x 100
Subtract the new number by the original number
91 - 431 = -340
-340 ÷ 431 = -0.7888631090487239
-0.7888631090487239 x 100 = -78.89%