condition mean min max ZT0-3 3.2095616666666666 2.7467099999999998 3.798725 ZT4-7 1.873715 1.873715 1.873715 ZT8-11 4.280595 4.280595 4.280595 ZT12-15 5.483745 4.352625 6.614865 ZT16-19 4.588525 4.588525 4.588525 ZT20-23 5.311045 5.311045 5.311045