-36.01% is the change from 997 to 638
Calculation steps:
[( 638 - 997 ) ÷ 997] x 100 = -36.01%
Formula
Percentage change = [(638 - 997) / 997] x 100
Subtract the new number by the original number
638 - 997 = -359
-359 ÷ 997 = -0.3600802407221665
-0.3600802407221665 x 100 = -36.01%