condition mean min max ZT0-3 22.349999999999998 22.349999999999998 22.349999999999998 ZT4-7 3.2 3.2 3.2 ZT8-11 29.55 29.55 29.55 ZT12-15 7.1499999999999995 7.1499999999999995 7.1499999999999995 ZT16-19 12.649999999999999 12.649999999999999 12.649999999999999 ZT20-23 5.1 5.1 5.1