-76.53% is the change from 639 to 150
Calculation steps:
[( 150 - 639 ) ÷ 639] x 100 = -76.53%
Formula
Percentage change = [(150 - 639) / 639] x 100
Subtract the new number by the original number
150 - 639 = -489
-489 ÷ 639 = -0.7652582159624414
-0.7652582159624414 x 100 = -76.53%