-89% is the change from 309 to 34
Calculation steps:
[( 34 - 309 ) ÷ 309] x 100 = -89%
Formula
Percentage change = [(34 - 309) / 309] x 100
Subtract the new number by the original number
34 - 309 = -275
-275 ÷ 309 = -0.889967637540453
-0.889967637540453 x 100 = -89%