-61.97% is the change from 639 to 243
Calculation steps:
[( 243 - 639 ) ÷ 639] x 100 = -61.97%
Formula
Percentage change = [(243 - 639) / 639] x 100
Subtract the new number by the original number
243 - 639 = -396
-396 ÷ 639 = -0.6197183098591549
-0.6197183098591549 x 100 = -61.97%