condition mean min max ZT0-3 12.163924999999999 11.5509 12.77695 ZT4-7 11.9689 11.9689 11.9689 ZT8-11 10.10586 10.10586 10.10586 ZT12-15 0 0 0 ZT16-19 9.556075 9.556075 9.556075 ZT20-23 11.475950000000001 11.475950000000001 11.475950000000001