condition mean min max ZT0-3 16.351058 16.351058 16.351058 ZT4-7 15.760164999999999 15.760164999999999 15.760164999999999 ZT8-11 14.927482999999999 14.927482999999999 14.927482999999999 ZT12-15 24.954376500000002 24.954376500000002 24.954376500000002 ZT16-19 18.0268855 18.0268855 18.0268855 ZT20-23 18.05749 18.05749 18.05749