condition mean min max ZT0-3 6640.731812 6640.731812 6640.731812 ZT4-7 6242.7987955 6242.7987955 6242.7987955 ZT8-11 6479.8271685 6479.8271685 6479.8271685 ZT12-15 5356.9347675 5356.9347675 5356.9347675 ZT16-19 4683.2818824999995 4683.2818824999995 4683.2818824999995 ZT20-23 4191.196704 4191.196704 4191.196704