AUGUSTA – Maine is doing at or above the national average in key economic measurements that make up the Index of State Economic Momentum, and that is being called good news. But, some economists say, the economic snapshot may not be a trend.

“It’s so nice to see a report come out where we are actually performing above the national average, and outperforming four of the six New England states, ” said State Economist Laurie LaChance. “I think it is a good opportunity to celebrate at least to a certain extent what is going on in Maine. We have finally turned the corner and [are] starting to see some lift.”

The Index of State Economic Momentum ranks states based on their most recent performance in three key measures: population growth, personal in-come growth and employment growth. Maine ranked 22nd in the latest index, which was released last month by State Policy Reports, a Washington-based group funded by the National Governors Association and the National Conference of State Legislatures.

“It is indeed good news,” said Kit St. John, executive director of the Maine Center for Economic Policy. “Lower unemployment than the national average, lower unemployment than the New England average and greater job growth than most of New England and that is a big turnaround from, say, 10 years ago.”

St. John’s group has been critical of some national economic rankings, but he said this study certainly passes muster. He said it uses known data sources such as the Census Bureau and the U.S. Department of Labor to create an index that is a tool in measuring economic health.

“These are statewide averages,” he said, “so that suggests that the southern Maine economy is even stronger when compared to Boston and the rest of the country. It suggests to me the southern Maine economy is really strong.”

Maine had the 12th-highest increase in personal income in the index study at 5.9 percent, above the national average of 5.2 percent. The state also ranked 12th with an unemployment rate of 4.1 percent, again below the national average of 5.6 percent. The state’s employment numbers were up nine-tenths of a percent, the same as the national average.

“Although we have these good numbers in terms of employment and personal income, I think we need to investigate a little bit deeper the structural underpinnings of the economy,” said University of Maine economics professor James Breece. “We can have employment gains, but it might be more in the low-paid service sector than in the high-paid manufacturing jobs.”

Breece, the director of the Office of Policy Research and Analysis for the university, said he is concerned the measure is only a snapshot of economic conditions and may not be an indication of overall economic vitality. For example, federal benefits such as food stamps are considered income and may have inflated the personal income growth number.

But St. John said there is other evidence to bolster the index findings. He said tax revenues are above estimates and the state ended the budget year with a surplus. He also said while Maine lost jobs during the recession, the losses were not as severe as in most other states.

“We have regained our peak employment levels,” said LaChance. “Many other states are still struggling to do that in the rest of New England.”

She said that while the index news is positive, Maine still has to catch up with other New England states. She said overall income levels in the state are below both the New England and national levels, even though they are improving.