condition mean min max ZT0-3 10.624095 10.624095 10.624095 ZT4-7 11.102624500000001 11.102624500000001 11.102624500000001 ZT8-11 11.4461635 11.4461635 11.4461635 ZT12-15 10.6997985 10.6997985 10.6997985 ZT16-19 8.7733115 8.7733115 8.7733115 ZT20-23 9.198515 9.198515 9.198515