condition mean min max ZT0-3 255.539749 255.539749 255.539749 ZT4-7 242.575984 242.575984 242.575984 ZT8-11 228.7610835 228.7610835 228.7610835 ZT12-15 223.662684 223.662684 223.662684 ZT16-19 250.04976299999998 250.04976299999998 250.04976299999998 ZT20-23 254.18818599999997 254.18818599999997 254.18818599999997