-78.73% is the change from 644 to 137
Calculation steps:
[( 137 - 644 ) ÷ 644] x 100 = -78.73%
Formula
Percentage change = [(137 - 644) / 644] x 100
Subtract the new number by the original number
137 - 644 = -507
-507 ÷ 644 = -0.7872670807453416
-0.7872670807453416 x 100 = -78.73%