condition mean min max ZT0-3 21.75 21.75 21.75 ZT4-7 8.6 8.6 8.6 ZT8-11 53.199999999999996 53.199999999999996 53.199999999999996 ZT12-15 16.85 16.85 16.85 ZT16-19 48.449999999999996 48.449999999999996 48.449999999999996 ZT20-23 41.599999999999994 41.599999999999994 41.599999999999994