-73% is the change from 300 to 81
Calculation steps:
[( 81 - 300 ) ÷ 300] x 100 = -73%
Formula
Percentage change = [(81 - 300) / 300] x 100
Subtract the new number by the original number
81 - 300 = -219
-219 ÷ 300 = -0.73
-0.73 x 100 = -73%
Example