condition mean min max ZT0-3 1.34572225 1.2509545 1.4404899999999998 ZT4-7 0.91058 0.91058 0.91058 ZT8-11 0.52751 0.52751 0.52751 ZT12-15 1.070872375 0.96995475 1.1717899999999999 ZT16-19 1.4367353333333333 1.2755733333333332 1.5978973333333333 ZT20-23 0 0 0