-33.54% is the change from 644 to 428
Calculation steps:
[( 428 - 644 ) ÷ 644] x 100 = -33.54%
Formula
Percentage change = [(428 - 644) / 644] x 100
Subtract the new number by the original number
428 - 644 = -216
-216 ÷ 644 = -0.33540372670807456
-0.33540372670807456 x 100 = -33.54%