condition mean min max ZT0-3 11.0447175 9.08014 13.009295 ZT4-7 22.91525 22.91525 22.91525 ZT8-11 31.578249999999997 31.578249999999997 31.578249999999997 ZT12-15 0 0 0 ZT16-19 31.621249999999996 31.621249999999996 31.621249999999996 ZT20-23 19.3158 19.3158 19.3158