condition mean min max ZT0-3 1.47635771575 0.528388865 2.4243265665 ZT4-7 4.172860122 3.9266175555 4.419102688500001 ZT8-11 4.932399604 4.1027951395 5.7620040685 ZT12-15 8.3375199615 6.8872298380000005 9.787810085 ZT16-19 11.133468717500001 10.842655015 11.42428242 ZT20-23 13.79418746 12.83655058 14.75182434