-23.81% is the change from 21 to 16
Calculation steps:
[( 16 - 21 ) ÷ 21] x 100 = -23.81%
Formula
Percentage change = [(16 - 21) / 21] x 100
Subtract the new number by the original number
16 - 21 = -5
-5 ÷ 21 = -0.23809523809523808
-0.23809523809523808 x 100 = -23.81%