condition mean min max ZT0-3 7.664255000000001 7.664255000000001 7.664255000000001 ZT4-7 5.259875 5.259875 5.259875 ZT8-11 4.2741050000000005 4.2741050000000005 4.2741050000000005 ZT12-15 4.159560000000001 4.159560000000001 4.159560000000001 ZT16-19 5.677725000000001 5.677725000000001 5.677725000000001 ZT20-23 7.34462 7.34462 7.34462