condition mean min max ZT0-3 597.428292 597.428292 597.428292 ZT4-7 743.3068860000001 743.3068860000001 743.3068860000001 ZT8-11 209.0790775 209.0790775 209.0790775 ZT12-15 42.79745199999999 42.79745199999999 42.79745199999999 ZT16-19 51.271418499999996 51.271418499999996 51.271418499999996 ZT20-23 263.6150035 263.6150035 263.6150035