condition mean min max ZT0-3 8.18066 8.18066 8.18066 ZT4-7 5.91935 5.91935 5.91935 ZT8-11 6.429315000000001 6.429315000000001 6.429315000000001 ZT12-15 6.00613 6.00613 6.00613 ZT16-19 7.66569 7.66569 7.66569 ZT20-23 8.071005 8.071005 8.071005