condition mean min max ZT0-3 170.647121 170.647121 170.647121 ZT4-7 232.10097100000002 232.10097100000002 232.10097100000002 ZT8-11 253.63457499999998 253.63457499999998 253.63457499999998 ZT12-15 257.213819 257.213819 257.213819 ZT16-19 265.0147915 265.0147915 265.0147915 ZT20-23 290.30471450000005 290.30471450000005 290.30471450000005