condition mean min max ZT0-3 1.9514775 1.8752 2.027755 ZT4-7 1.535417 1.535417 1.535417 ZT8-11 1.2737850000000002 1.2737850000000002 1.2737850000000002 ZT12-15 0 0 0 ZT16-19 1.992305 1.992305 1.992305 ZT20-23 3.0474300000000003 3.0474300000000003 3.0474300000000003