condition mean min max ZT0-3 14.554152728250001 13.002984106500001 16.10532135 ZT4-7 8.47358011225 6.7223725089999995 10.2247877155 ZT8-11 7.4782242495 6.2866345915 8.6698139075 ZT12-15 3.6301384485 2.5124575415 4.7478193555 ZT16-19 11.357559203000001 8.476851751000002 14.238266655 ZT20-23 23.59110768 19.8662821 27.315933259999998