condition mean min max ZT0-3 4.946525 4.946525 4.946525 ZT4-7 4.584625 4.584625 4.584625 ZT8-11 3.434155 3.434155 3.434155 ZT12-15 3.9010350000000003 3.9010350000000003 3.9010350000000003 ZT16-19 4.883895 4.883895 4.883895 ZT20-23 6.305605 6.305605 6.305605