condition mean min max ZT0-3 4.40017 3.065495 5.105085 ZT4-7 6.61689 6.61689 6.61689 ZT8-11 16.41035 16.41035 16.41035 ZT12-15 3.8010875000000004 2.94654 4.655635 ZT16-19 4.202455 4.202455 4.202455 ZT20-23 4.240355 4.240355 4.240355