condition mean min max ZT0-3 4.33902 4.1463 4.53174 ZT4-7 4.423995 4.423995 4.423995 ZT8-11 2.99861 2.99861 2.99861 ZT12-15 0 0 0 ZT16-19 6.922835 6.922835 6.922835 ZT20-23 6.19605 6.19605 6.19605