Monroe County property values in the past year have dropped anywhere from 9 percent to nearly 24 percent, depending on location, according to the Property Appraiser's Office estimates released Tuesday.

Appraisers this week released their estimated property tax assessments so municipalities, county governments, school districts and other taxing agencies can begin working on their 2009-10 fiscal year budgets, which start in October.

The $3 billion drop to $22.94 billion reflects the drop in value between Jan. 1, 2008, and Jan. 1, 2009, according to Karl Borglum, a senior Monroe County government property appraiser.

The assessment won't be finalized until later this month, but assuming it remains unchanged, the tax roll decrease means the county government will be forced to either sharply raise the tax rate or otherwise live with declining revenue -- a move that would force tough decisions on which services to cut.

Of the larger Florida Keys cities, property values in the city of Marathon dropped the most, going from $2.8 billion in 2008 to $2.3 billion in 2009, an 18.6 percent drop.

Among the smaller Keys cities, the smallest, Layton, dropped 23.8 percent, going from $77.8 million to $59.3 million.

Likewise, Layton's neighbor, Key Colony Beach, also saw a reduction. Key Colony Beach dropped 20 percent, going from almost $797 million to $637 million, according to the Property Appraiser's Office.

Key West saw the least drop in value, with a $6.6 billion assessment in 2008 to a $6 billion assessment in 2009, records show. The drop is an 8.9 percent reduction, according to the Property Appraiser's Office.

Assessed value of property in unincorporated Monroe County fell from $26.2 billion to $22.9 billion, a 12.6 percent drop, according to the Property Appraiser's Office. Homes and commercial property in the school district taxing domain dropped 12.5 percent, going from $26.7 billion to $23.3 billion. Property values in Islamorada also dropped 12.5 percent, from $3.5 billion in 2008 to $3 billion in 2009.

The reduction is "comparable to what other counties in the state are experiencing," Borglum said. "For the most part, it is due to a declining market."

The Appraiser's Office has sent each of the taxing agencies the estimates. The office will continue working on the estimates before having them certified this fall so agencies can set their property taxes and send out notices to property owners, Borglum said.

This would be the second year the June estimates fell below the previous year's assessed value. Monroe County's 2008 tax base declined by $1.2 billion from 2007, according to last year's June 1 estimate by the Property Appraiser's Office.

Staff writer Robert Silk contributed to this report.

tohara@keysnews.com