condition mean min max ZT0-3 12.18245705 11.62685237 12.73806173 ZT4-7 14.607468542249999 11.4012685595 17.813668524999997 ZT8-11 14.486972155 12.682332419999998 16.291611890000002 ZT12-15 8.83151678375 7.038196129999999 10.6248374375 ZT16-19 9.149393731249999 7.6986097325000005 10.600177729999999 ZT20-23 14.2038876775 12.970085274999999 15.43769008