condition mean min max ZT0-3 1.234875 1.234875 1.234875 ZT4-7 0.5331715 0.5331715 0.5331715 ZT8-11 0.4654235 0.4654235 0.4654235 ZT12-15 1.3456299999999999 1.3456299999999999 1.3456299999999999 ZT16-19 3.52058 3.52058 3.52058 ZT20-23 1.7550400000000002 1.7550400000000002 1.7550400000000002