condition mean min max ZT0-3 9.6561325 9.574605 9.73766 ZT4-7 8.005495 8.005495 8.005495 ZT8-11 9.861885000000001 9.861885000000001 9.861885000000001 ZT12-15 0 0 0 ZT16-19 9.993085 9.993085 9.993085 ZT20-23 11.1703 11.1703 11.1703