condition mean min max ZT0-3 22.64724 22.64724 22.64724 ZT4-7 18.396954 18.396954 18.396954 ZT8-11 14.109022 14.109022 14.109022 ZT12-15 11.857217 11.857217 11.857217 ZT16-19 13.757025500000001 13.757025500000001 13.757025500000001 ZT20-23 16.607673 16.607673 16.607673