-93.7% is the change from 270 to 17
Calculation steps:
[( 17 - 270 ) ÷ 270] x 100 = -93.7%
Formula
Percentage change = [(17 - 270) / 270] x 100
Subtract the new number by the original number
17 - 270 = -253
-253 ÷ 270 = -0.937037037037037
-0.937037037037037 x 100 = -93.7%