-76.18% is the change from 340 to 81
Calculation steps:
[( 81 - 340 ) ÷ 340] x 100 = -76.18%
Formula
Percentage change = [(81 - 340) / 340] x 100
Subtract the new number by the original number
81 - 340 = -259
-259 ÷ 340 = -0.7617647058823529
-0.7617647058823529 x 100 = -76.18%