condition mean min max ZT0-3 13.779833333333332 13.779833333333332 13.779833333333332 ZT4-7 10.55081 10.55081 10.55081 ZT8-11 10.818249999999999 10.818249999999999 10.818249999999999 ZT12-15 15.99515 15.99515 15.99515 ZT16-19 17.2947 17.2947 17.2947 ZT20-23 20.665399999999998 20.665399999999998 20.665399999999998