condition mean min max ZT0-3 2.9585425 2.4152449999999996 3.50184 ZT4-7 2.81389 2.81389 2.81389 ZT8-11 2.20852 2.20852 2.20852 ZT12-15 0 0 0 ZT16-19 2.804685 2.804685 2.804685 ZT20-23 3.163565 3.163565 3.163565