condition mean min max ZT0-3 2397.257417 2397.257417 2397.257417 ZT4-7 2958.412592 2958.412592 2958.412592 ZT8-11 3438.257426 3438.257426 3438.257426 ZT12-15 3636.035078 3636.035078 3636.035078 ZT16-19 3798.929789 3798.929789 3798.929789 ZT20-23 5661.6904525 5661.6904525 5661.6904525