condition mean min max ZT0-3 6.76851 6.76851 6.76851 ZT4-7 7.3176950000000005 7.3176950000000005 7.3176950000000005 ZT8-11 6.016019999999999 6.016019999999999 6.016019999999999 ZT12-15 5.866625 5.866625 5.866625 ZT16-19 7.26856 7.26856 7.26856 ZT20-23 6.81781 6.81781 6.81781