condition mean min max ZT0-3 5.959152139 4.010372874 7.907931404 ZT4-7 13.5072161125 11.875604840000001 15.138827384999999 ZT8-11 10.963093341 10.3447556955 11.5814309865 ZT12-15 6.48142962425 5.947011625 7.0158476235 ZT16-19 11.6131662835 7.686664837 15.53966773 ZT20-23 29.371021365 23.71687745 35.02516528