-16.05% is the change from 81 to 68
Calculation steps:
[( 68 - 81 ) ÷ 81] x 100 = -16.05%
Formula
Percentage change = [(68 - 81) / 81] x 100
Subtract the new number by the original number
68 - 81 = -13
-13 ÷ 81 = -0.16049382716049382
-0.16049382716049382 x 100 = -16.05%