condition mean min max ZT0-3 6719.232057 6719.232057 6719.232057 ZT4-7 6354.067188 6354.067188 6354.067188 ZT8-11 6335.9164375 6335.9164375 6335.9164375 ZT12-15 6959.9033225 6959.9033225 6959.9033225 ZT16-19 7297.295049 7297.295049 7297.295049 ZT20-23 7137.182911 7137.182911 7137.182911