condition mean min max ZT0-3 9.1382535435 8.483366497 9.79314059 ZT4-7 23.74960068025 13.2275192855 34.271682075 ZT8-11 83.8156574125 63.677957515 103.95335731 ZT12-15 49.0056600875 27.2522879 70.759032275 ZT16-19 16.1207924775 13.10122791 19.140357045000002 ZT20-23 7.08720933925 6.179871764 7.994546914500001