condition mean min max ZT0-3 3.1983706080000003 2.355536235 4.041204981 ZT4-7 6.29105049825 5.2627329925 7.319368003999999 ZT8-11 10.36462270025 7.780625420500001 12.94861998 ZT12-15 8.636006135 8.390645733500001 8.8813665365 ZT16-19 6.98618214325 6.209109086 7.7632552005 ZT20-23 9.556131904499999 9.177502348500001 9.934761460499999