condition mean min max ZT0-3 18.802666666666667 12.44335 23.06825 ZT4-7 12.07625 12.07625 12.07625 ZT8-11 13.532900000000001 13.532900000000001 13.532900000000001 ZT12-15 17.598575 15.25455 19.9426 ZT16-19 19.3164 19.3164 19.3164 ZT20-23 27.5721 27.5721 27.5721