If one looked just at the current vacancy rates in Anchorage's office buildings, it would be hard to tell that the city is getting bitten by the global recession.

Nationally, while vacancies at office buildings have skyrocketed as a result of the troubled economy -- exceeding 15 percent in the first three months of 2009 -- the supply of office space has actually tightened somewhat in Anchorage.

"We are a little different up here," said Per Bjorn-Roli, an Anchorage commercial appraiser, who tried to explain the anomaly at a recent luncheon for building owners and managers in downtown Anchorage.

The big surprise: The supply of office space in Anchorage is tighter now than it was at this time last year despite the clear evidence -- layoffs, for example -- that the city's economy has softened in recent months, Bjorn-Roli said.

In the city's most expensive office buildings, the current vacancy rate is about 2 percent compared with last year's 4 percent, according to a survey Bjorn-Roli did for the Anchorage chapter of the Building Owners & Managers Association. He also found that the vacancy rate in less-expensive office buildings has declined somewhat.

Those vacancy rates indicate that the local market for office buildings is stable and healthy, said Bjorn-Roli, who predicts that vacancies will increase slightly in the coming year but remain at a healthy level.

Low vacancy rates are good for landlords, but they put upward pressure on lease rates for tenants, he said.

The tight vacancies come despite the recent wave of layoffs at some local companies, including Conoco Phillips and FedEx, the downturn in tourism bookings, and the slowdown in mining and oil and gas exploration around the state.

So why is the local office market -- the hub for most of Alaska's large businesses -- not suffering more? And is that just temporary?

Here's what Bjorn-Roli thinks.

Anchorage job losses this year may have not lessened the tight supply of office space so far this year because those layoffs might be targeting non-office staff -- oil field workers, for example -- and also because some large companies own their own buildings, he said.

One company, Chevron Corp., previously occupied and leased extra space in its six-story Unocal building in downtown. But this year, Chevron moved to Midtown and it says it isn't offering any space this year in the downtown building while it decides what to do with it. If the Unocal building had been leased, local vacancy rates would have been a tad higher, but still quite low, Bjorn-Roli said.

Another reason for the continuing tight supply is "residual momentum" from last year's economic growth in Anchorage, he said. The momentum stemmed in part from record-high oil prices and the launching of two competing North Slope gas pipeline projects.

That's a reasonable explanation, said Neal Fried, a state economist who studies Anchorage employment trends.

He warned, though, that looking at last year is not a good way to predict this year's economic performance, which is struggling so far from volcano-induced suspensions of international cargo flights and the slashing of corporate budgets due to low commodity prices.

In contrast, last year was just a good year, Fried said.

"Everything was growing. Personal income increased over 9 percent (statewide), the biggest increase since the oil spill" in 1989, Fried said.

It could just be taking longer for Anchorage to react to the global recession, he said.