Personal Property Tax Assessments--2009

I received my 2009 personal property tax bill in this afternoon's mail. It was quite a bit higher than my 2008 bill.

That was unexpected because although I bought and sold some vehicles in 2008, I thought it would balance out. I sold a 1953 Chevrolet pickup with an assessed valuation of $100 and I bought a 1947 Jeep CJ2A with an assessed valuation of $100.00.So it all balances out, or so I thought.
Then I dug out my personal property tax detail.

In 2007, my 2003 pontoon boat was assessed at $1750.00.
In 2008, my 2003 pontoon boat was assessed at $2090.00.
In 2009, my 2003 pontoon boat was assessed at $2880.00.
In 2006, my 1998 Honda was assessed at $1950.00.
In 2007, my 1998 Honda was assessed at $1410.00.
In 2008, my 1998 Honda was assessed at $1340.00.
In 2009, my 1998 Honda was assessed at $1580.00.My daily driver, the blue S-10, in each successive year since I have owned it, the assessed valuation has decreased, as expected.
In 2006, my 2001 S-10 was assessed at $2040.00.
In 2007, my 2001 S-10 was assessed at $1850.00.
In 2008, my 2001 S-10 was assessed at $1660.00.
In 2009, my 2001 S-10 was assessed at $1420.00.How to raise taxes without raising taxes? Raise the assessed value. I can sort of understand real estate appreciating and every vehicle I owned depreciated except for the 1998 Honda and the 2003 Pontoon. I wonder if I filled out the form wrong?

I guess I'll be calling the assessor's office on Monday.