condition mean min max ZT0-3 21.825285 10.730955000000002 41.35395 ZT4-7 11.85015 11.85015 11.85015 ZT8-11 3.1626700000000003 3.1626700000000003 3.1626700000000003 ZT12-15 7.2756725 6.3899799999999995 8.161365 ZT16-19 4.01994 4.01994 4.01994 ZT20-23 4.5815850000000005 4.5815850000000005 4.5815850000000005