condition mean min max ZT0-3 3.83922 3.83922 3.83922 ZT4-7 2.41925 2.41925 2.41925 ZT8-11 3.46002 3.46002 3.46002 ZT12-15 4.855575 4.855575 4.855575 ZT16-19 5.26841 5.26841 5.26841 ZT20-23 4.68347 4.68347 4.68347