condition mean min max ZT0-3 4.194660000000001 3.07636 5.31296 ZT4-7 3.01999 3.01999 3.01999 ZT8-11 2.252705 2.252705 2.252705 ZT12-15 0 0 0 ZT16-19 3.3442049999999997 3.3442049999999997 3.3442049999999997 ZT20-23 3.5953 3.5953 3.5953