On the back of an almost 20 percent decrease in assessed home values, the people of Issaquah will pay an average of 2 percent less property tax than they did last year.

But in Sammamish, a similar fall in assessed values has been countered by an increase in school levy payments and the amount collected by the city to result in a marginal increase in taxes for 2010 – an average of $64 for the year.

In 2009, the average value of an Issaquah home as assessed by the King County Assessor’s Office was $606,800. A year later, it’s $493,200, an 18.7 percent decrease, reflecting the downturn in the economy and the housing sales market.

As a result, the owner of a home at that price will pay $110 less in taxes this year than they did in 2009, despite an increase in levy payments for the voter-approved Issaquah School District levies. The most sizable increase for homeowners in the Issaquah School District was not, in fact, the new levies passed last year, but a .79 percent increase in payments on the construction bond approved in 2006.

In Sammamish, the average assessed value fell from $654,100 in 2009 to $548,900 in 2010.

But the owner of a $548,000 Sammamish home in the Issaquah School District will be ask to pay $64.35 more in taxes this year, with the rate rising to 11.86 percent, up from 9.85 percent last year.

The figures for a Sammamish home in the Lake Washington School District were not available, though they were expected to be lower than their Issaquah School District neighbors as Lake Washington School District voters this year rejected a construction bond proposal to help reduce overcrowding in schools.

The assessor’s office uses comparable sales within the past year to estimate the value of a property, and includes some forecasting of future trends in the market. It is acknowledged there is some lag time between the county’s assessment of home prices and the active market.

Talking with The Reporter during a visit to Issaquah in May, new King County Assessor Lloyd Hara said he had made an administrative decision to change the way house prices were assessed, and believed he had captured a more accurate picture of the region’s property values.

According to Hara, the previous King County Assessor, Scott Noble, used an average of the previous three years of house sales.

“There was a fair amount of lag associated with this,” Hara said.

Particularly in 2009, when home values were reflecting the booming economy of 2006-2008, but residents pocketbooks were very much mired in a historic recession.

In that year, the assessors office received more than 13,000 assessment appeals – substantially more than the 3 – 4,00 that is typical.

“Quite frankly, up until the boom ended, nobody cared,” Hara said.

He said this year he had taken account of “trending” – including home sales for the first few months of 2010 and using market analytics, to make values a closer reflection of the market.

“I think we’ve got our assessments pretty close (to the market) this year,” he said, adding that his office had noticed the free fall in home prices had eased up. “For the first month or two this year we are seeing a flatline. I’m not sure exactly why this is. Some realtors say it has to do with the first time homebuyers grant.”

For the first time, this year’s sales histories included foreclosures and short sales, which had traditionally been excluded.

“We now have whole developments being sold under these conditions,” Hara said. “It’s more than an anomaly in some cases – it’s the norm in some cases. This will have somewhat of a depressive effect.”

In making the property value assessments upon which our property taxes are based, the assessors office divides the county into 100 areas. Issaquah alone is comprised of three areas, which vary slightly based on school district, library, fire service, and other boundaries.

Higher or lower assessed values don’t necessarily equate to higher or lower taxes. The county calculates the amount of tax revenue it is allowed to collect, and then divides that amount over the assessed valuations in its territories. State law limits how much money districts can collect without a vote. As we have seen this year, when assessed values fall, the tax rate typically goes up, resulting in a marginal positive or negative change.

Homeowners have 60 days from the time they receive their property valuations to launch an appeal with the assessors office.