condition mean min max ZT0-3 1.8715549999999999 1.8715549999999999 1.8715549999999999 ZT4-7 2.1170600000000004 2.1170600000000004 2.1170600000000004 ZT8-11 6.7730049999999995 6.7730049999999995 6.7730049999999995 ZT12-15 15.26175 15.26175 15.26175 ZT16-19 26.4422 26.4422 26.4422 ZT20-23 3.7231300000000003 3.7231300000000003 3.7231300000000003