condition mean min max ZT0-3 8.279735 8.279735 8.279735 ZT4-7 9.892528500000001 9.892528500000001 9.892528500000001 ZT8-11 9.528633 9.528633 9.528633 ZT12-15 8.7307935 8.7307935 8.7307935 ZT16-19 8.967951 8.967951 8.967951 ZT20-23 8.594561500000001 8.594561500000001 8.594561500000001