condition mean min max ZT0-3 10.539829425499999 9.260695596999998 11.818963254 ZT4-7 15.77718706 12.32163004 19.23274408 ZT8-11 18.745256623333333 17.536809956666666 19.95370329 ZT12-15 10.8109861455 9.581248145666667 12.040724145333334 ZT16-19 7.5773389855 7.0840144160000005 8.070663555 ZT20-23 5.820526052666667 5.539104312 6.101947793333333