condition mean min max ZT0-3 4.59889 4.59889 4.59889 ZT4-7 5.134869999999999 5.134869999999999 5.134869999999999 ZT8-11 4.45111 4.45111 4.45111 ZT12-15 3.7606200000000003 3.7606200000000003 3.7606200000000003 ZT16-19 2.7674 2.7674 2.7674 ZT20-23 3.36616 3.36616 3.36616