-73.6% is the change from 644 to 170
Calculation steps:
[( 170 - 644 ) ÷ 644] x 100 = -73.6%
Formula
Percentage change = [(170 - 644) / 644] x 100
Subtract the new number by the original number
170 - 644 = -474
-474 ÷ 644 = -0.7360248447204969
-0.7360248447204969 x 100 = -73.6%