condition mean min max ZT0-3 0.588337 0.588337 0.588337 ZT4-7 0.476101 0.476101 0.476101 ZT8-11 2.624605 2.624605 2.624605 ZT12-15 6.05793 6.05793 6.05793 ZT16-19 3.248765 3.248765 3.248765 ZT20-23 1.36213 1.36213 1.36213