-19.32% is the change from 792 to 639
Calculation steps:
[( 639 - 792 ) ÷ 792] x 100 = -19.32%
Formula
Percentage change = [(639 - 792) / 792] x 100
Subtract the new number by the original number
639 - 792 = -153
-153 ÷ 792 = -0.19318181818181818
-0.19318181818181818 x 100 = -19.32%