-21.66% is the change from 217 to 170
Calculation steps:
[( 170 - 217 ) ÷ 217] x 100 = -21.66%
Formula
Percentage change = [(170 - 217) / 217] x 100
Subtract the new number by the original number
170 - 217 = -47
-47 ÷ 217 = -0.21658986175115208
-0.21658986175115208 x 100 = -21.66%