condition mean min max ZT0-3 17.776899999999998 17.776899999999998 17.776899999999998 ZT4-7 14.971599999999999 14.971599999999999 14.971599999999999 ZT8-11 13.311399999999999 13.311399999999999 13.311399999999999 ZT12-15 15.27735 15.27735 15.27735 ZT16-19 18.75365 18.75365 18.75365 ZT20-23 16.4927 16.4927 16.4927