condition mean min max ZT0-3 25.634725 25.4361 25.83335 ZT4-7 24.4615 24.4615 24.4615 ZT8-11 22.56635 22.56635 22.56635 ZT12-15 0 0 0 ZT16-19 22.719250000000002 22.719250000000002 22.719250000000002 ZT20-23 24.789450000000002 24.789450000000002 24.789450000000002