condition mean min max ZT0-3 29.165449 29.165449 29.165449 ZT4-7 24.915921500000003 24.915921500000003 24.915921500000003 ZT8-11 32.5782435 32.5782435 32.5782435 ZT12-15 21.628453999999998 21.628453999999998 21.628453999999998 ZT16-19 26.270193499999998 26.270193499999998 26.270193499999998 ZT20-23 18.192692 18.192692 18.192692