-69.64% is the change from 639 to 194
Calculation steps:
[( 194 - 639 ) ÷ 639] x 100 = -69.64%
Formula
Percentage change = [(194 - 639) / 639] x 100
Subtract the new number by the original number
194 - 639 = -445
-445 ÷ 639 = -0.6964006259780907
-0.6964006259780907 x 100 = -69.64%