1) old: 4 ; new: 5 = (5-4)/4 = 1/4 = 25% increase
2) old: 1.0 ; new: 1.3 = (1.3 - 1.0)/1.0 = 0.30/1 = 30% increase
3) old: 15 ; new: 12 = (12-15)/15 = 3/15 = 1/5 = 20% decrease
4) old: 30 ; new: 18 = (18-30)/30 = 12/30 = 2/5 = 40% decrease
5) old: 60 ; new: 63 = (63-60)/60 = 3/60 = 1/20 = 5% increase
6) old: 160 ; new: 136 = (136-160)/160 = 24/160 = 12/80 = 3/20 = 15% decrease
7) old: 7.7 ; new: 10.5 = (10.5-7.7)/7.7 = 2.8/7.7 = 36% increase
8) old: 9.6 ; new: 5.9 = (5.9-9.6)/9.6 = 3.7/9.6 = 39% decrease
