condition mean min max ZT0-3 15.5868 15.241 15.9326 ZT4-7 13.3697 13.3697 13.3697 ZT8-11 8.585529999999999 8.585529999999999 8.585529999999999 ZT12-15 0 0 0 ZT16-19 23.60875 23.60875 23.60875 ZT20-23 18.72835 18.72835 18.72835