condition mean min max ZT0-3 2.1048475 2.0686299999999997 2.1410649999999998 ZT4-7 1.80777 1.80777 1.80777 ZT8-11 1.32991 1.32991 1.32991 ZT12-15 0 0 0 ZT16-19 1.537395 1.537395 1.537395 ZT20-23 1.932385 1.932385 1.932385