condition mean min max ZT0-3 20.388550000000002 20.388550000000002 20.388550000000002 ZT4-7 13.12405 13.12405 13.12405 ZT8-11 12.45235 12.45235 12.45235 ZT12-15 12.27575 12.27575 12.27575 ZT16-19 21.7235 21.7235 21.7235 ZT20-23 21.209200000000003 21.209200000000003 21.209200000000003