condition mean min max ZT0-3 11.805043 11.805043 11.805043 ZT4-7 12.150766 12.150766 12.150766 ZT8-11 13.549756 13.549756 13.549756 ZT12-15 10.702213 10.702213 10.702213 ZT16-19 12.394701000000001 12.394701000000001 12.394701000000001 ZT20-23 12.1729345 12.1729345 12.1729345