condition mean min max ZT0-3 12.497516666666666 11.0427 14.258 ZT4-7 9.53491 9.53491 9.53491 ZT8-11 13.016300000000001 13.016300000000001 13.016300000000001 ZT12-15 25.143875 24.50255 25.7852 ZT16-19 22.29815 22.29815 22.29815 ZT20-23 21.1574 21.1574 21.1574