condition mean min max ZT0-3 18.78405 18.78405 18.78405 ZT4-7 14.52785 14.52785 14.52785 ZT8-11 13.402149999999999 13.402149999999999 13.402149999999999 ZT12-15 11.012875000000001 11.012875000000001 11.012875000000001 ZT16-19 20.332900000000002 20.332900000000002 20.332900000000002 ZT20-23 20.65255 20.65255 20.65255