condition mean min max ZT0-3 25.852495 25.852495 25.852495 ZT4-7 26.6780295 26.6780295 26.6780295 ZT8-11 30.7780425 30.7780425 30.7780425 ZT12-15 24.480366 24.480366 24.480366 ZT16-19 23.8389005 23.8389005 23.8389005 ZT20-23 18.8776265 18.8776265 18.8776265