-94.05% is the change from 639 to 38
Calculation steps:
[( 38 - 639 ) ÷ 639] x 100 = -94.05%
Formula
Percentage change = [(38 - 639) / 639] x 100
Subtract the new number by the original number
38 - 639 = -601
-601 ÷ 639 = -0.9405320813771518
-0.9405320813771518 x 100 = -94.05%