-24.3% is the change from 321 to 243
Calculation steps:
[( 243 - 321 ) ÷ 321] x 100 = -24.3%
Formula
Percentage change = [(243 - 321) / 321] x 100
Subtract the new number by the original number
243 - 321 = -78
-78 ÷ 321 = -0.24299065420560748
-0.24299065420560748 x 100 = -24.3%