condition mean min max ZT0-3 4.17709 4.17709 4.17709 ZT4-7 2.3741950000000003 2.3741950000000003 2.3741950000000003 ZT8-11 2.949125 2.949125 2.949125 ZT12-15 4.719115 4.719115 4.719115 ZT16-19 6.4256150000000005 6.4256150000000005 6.4256150000000005 ZT20-23 4.14539 4.14539 4.14539