condition mean min max ZT0-3 15.459875 15.14525 15.7745 ZT4-7 18.5249 18.5249 18.5249 ZT8-11 25.91635 25.91635 25.91635 ZT12-15 0 0 0 ZT16-19 31.86765 31.86765 31.86765 ZT20-23 25.658549999999998 25.658549999999998 25.658549999999998