condition mean min max ZT0-3 4.11128 4.11128 4.11128 ZT4-7 2.86823 2.86823 2.86823 ZT8-11 3.635115 3.635115 3.635115 ZT12-15 4.41435 4.41435 4.41435 ZT16-19 6.12208 6.12208 6.12208 ZT20-23 4.96715 4.96715 4.96715