-31.16% is the change from 934 to 643
Calculation steps:
[( 643 - 934 ) ÷ 934] x 100 = -31.16%
Formula
Percentage change = [(643 - 934) / 934] x 100
Subtract the new number by the original number
643 - 934 = -291
-291 ÷ 934 = -0.31156316916488225
-0.31156316916488225 x 100 = -31.16%