-67.73% is the change from 251 to 81
Calculation steps:
[( 81 - 251 ) ÷ 251] x 100 = -67.73%
Formula
Percentage change = [(81 - 251) / 251] x 100
Subtract the new number by the original number
81 - 251 = -170
-170 ÷ 251 = -0.6772908366533864
-0.6772908366533864 x 100 = -67.73%