condition mean min max ZT0-3 11.334498333333332 7.37653 15.4272 ZT4-7 25.074199999999998 25.074199999999998 25.074199999999998 ZT8-11 20.06145 20.06145 20.06145 ZT12-15 13.286455 11.96745 14.605459999999999 ZT16-19 9.395405 9.395405 9.395405 ZT20-23 5.69219 5.69219 5.69219