condition mean min max ZT0-3 13.814213 13.814213 13.814213 ZT4-7 13.6032695 13.6032695 13.6032695 ZT8-11 15.4428455 15.4428455 15.4428455 ZT12-15 13.2629345 13.2629345 13.2629345 ZT16-19 13.6322805 13.6322805 13.6322805 ZT20-23 14.182341000000001 14.182341000000001 14.182341000000001