condition mean min max ZT0-3 3.2358550443333334 2.505875352 3.965834736666667 ZT4-7 8.7606540385 8.611966849 8.909341227999999 ZT8-11 4.349876281 3.2880118990000002 5.411740663 ZT12-15 2.3256227234999995 2.1724134029999997 2.478832044 ZT16-19 6.7430922251666665 3.184754198333333 10.301430252 ZT20-23 12.6283165225 11.550845292333333 13.705787752666666