condition mean min max ZT0-3 12.95 12.95 12.95 ZT4-7 5.7 5.7 5.7 ZT8-11 40.150000000000006 40.150000000000006 40.150000000000006 ZT12-15 10.200000000000001 10.200000000000001 10.200000000000001 ZT16-19 14.950000000000001 14.950000000000001 14.950000000000001 ZT20-23 45.849999999999994 45.849999999999994 45.849999999999994