-20.1% is the change from 806 to 644
Calculation steps:
[( 644 - 806 ) ÷ 806] x 100 = -20.1%
Formula
Percentage change = [(644 - 806) / 806] x 100
Subtract the new number by the original number
644 - 806 = -162
-162 ÷ 806 = -0.20099255583126552
-0.20099255583126552 x 100 = -20.1%