condition mean min max ZT0-3 22.712411 22.712411 22.712411 ZT4-7 20.199696 20.199696 20.199696 ZT8-11 21.3962785 21.3962785 21.3962785 ZT12-15 26.293308 26.293308 26.293308 ZT16-19 27.016195500000002 27.016195500000002 27.016195500000002 ZT20-23 24.8811865 24.8811865 24.8811865