condition mean min max ZT0-3 3.0264169485 1.996647122 4.0561867750000005 ZT4-7 8.135951670499999 7.4953392275 8.7765641135 ZT8-11 8.7373355545 7.567864611500001 9.9068064975 ZT12-15 30.671755739999995 23.846326164999997 37.497185314999996 ZT16-19 33.137229902499996 30.193031935 36.08142787 ZT20-23 30.732737505000003 29.45265521 32.0128198