condition mean min max ZT0-3 5.699999999999999 5.699999999999999 5.699999999999999 ZT4-7 1.4 1.4 1.4 ZT8-11 3.8 3.8 3.8 ZT12-15 12.1 12.1 12.1 ZT16-19 11.549999999999999 11.549999999999999 11.549999999999999 ZT20-23 33.1 33.1 33.1