condition mean min max ZT0-3 5.9913050000000005 5.9913050000000005 5.9913050000000005 ZT4-7 5.941535 5.941535 5.941535 ZT8-11 6.35375 6.35375 6.35375 ZT12-15 6.769025 6.769025 6.769025 ZT16-19 5.248545 5.248545 5.248545 ZT20-23 4.435835 4.435835 4.435835