-93.33% is the change from 15 to 1
Calculation steps:
[( 1 - 15 ) ÷ 15] x 100 = -93.33%
Formula
Percentage change = [(1 - 15) / 15] x 100
Subtract the new number by the original number
1 - 15 = -14
-14 ÷ 15 = -0.9333333333333333
-0.9333333333333333 x 100 = -93.33%