-19.9% is the change from 839 to 672
Calculation steps:
[( 672 - 839 ) ÷ 839] x 100 = -19.9%
Formula
Percentage change = [(672 - 839) / 839] x 100
Subtract the new number by the original number
672 - 839 = -167
-167 ÷ 839 = -0.19904648390941598
-0.19904648390941598 x 100 = -19.9%