condition mean min max ZT0-3 15.945225 15.945225 15.945225 ZT4-7 29.509367500000003 29.509367500000003 29.509367500000003 ZT8-11 29.145671 29.145671 29.145671 ZT12-15 25.1208685 25.1208685 25.1208685 ZT16-19 17.810288999999997 17.810288999999997 17.810288999999997 ZT20-23 15.002739 15.002739 15.002739