Americans Show Signs Of Worry After Burst Of Sept. 11 Optimism Majority still positive, but roundtrip describes slow fade in poll index.(A)(IBD/TIPP POLL)

Byline: BRIAN MITCHELL

After a burst of patriotism and rising hopes after Sept. 11, Americans are working hard to maintain their customary optimism.

The latest IBD/TIPP poll finds the National Outlook Index up from where it was a year ago -- before Sept. 11. It was in neutral territory -- just above 50 and trending downward -- before the attack.

It shot to 67.1 in the month after the attack and stayed above 60 for six months before settling to 53.4 now. That's still higher than it was all through the summer of 2001.

"America is an optimistic nation today, one year after 9-11," said Raghavan Mayur, president of TIPP, a unit of TechnoMetrica Market Intelligence and IBD's polling partner.

"Of the 21 groups we track, prior to 9-11, 11 groups were optimistic and 10 were pessimistic. Now 19 groups are optimistic," he said.

"Only two groups -- those age 65-plus and Democrats -- are pessimistic. Republicans and those age 18 to 24 are the most optimistic about the nation," he said.

The National Outlook Index has six component indices. Each takes …