condition mean min max ZT0-3 6.77324 6.77324 6.77324 ZT4-7 1.968525 1.968525 1.968525 ZT8-11 3.13686 3.13686 3.13686 ZT12-15 8.650925 8.650925 8.650925 ZT16-19 13.2 13.2 13.2 ZT20-23 11.6005 11.6005 11.6005