condition mean min max ZT0-3 12.4435775 11.006305000000001 13.880849999999999 ZT4-7 9.125255 9.125255 9.125255 ZT8-11 8.3146 8.3146 8.3146 ZT12-15 0 0 0 ZT16-19 12.493500000000001 12.493500000000001 12.493500000000001 ZT20-23 10.726785 10.726785 10.726785