Lauren Ritchie: Don’t let politicians fatten up on taxes.

Here’s the single thing you need to know about taxes this year: Elected types are ripping you off if they try to jack up your property tax rate by one iota.

It’s easy to make such a blank declaration because the value of properties in Central Florida took an impressive jump up this year, and taxes in this state are based on property values.

There’s no set amount per house that everyone pays. Rather, it’s calculated using a rate so that people who own flashy joints with elevators and infinity pools pay more than those in a 1965 single-wide back along a clay road in the Ocala National Forest.

The big picture is this simple: When the value of properties in a county — that’s called the tax roll — goes up, governments get to rake in more cash, often even if they actually lower the rate. How does this work? Here’s a primer.

Let’s say you own a house in Orlando worth $100,000 for tax purposes after homestead and other exemptions are deducted from its value. The tax rate in the City Beautiful is $6.65 for every $1,000 worth of taxable property.

Using the miracles of modern division and multiplication, we can learn that you’re paying $665 a year for police, fire, building inspections, parks and water service — you get the idea.

Now, let’s assume that the taxable value of that $100,000 house went up this year to, say, $112,340. If Orlando keeps the same tax rate, you’d pay $747.06 — about $82 more than the previous year — if it weren’t for the Save Our Homes amendment that caps increases in assessed value at 3 percent.

Such a homeowner still would pay $20 extra, for a bill of $685. But non-homesteaded properties such as businesses and rentals have a higher cap — 10 percent — and could see tax bills climb with the double whammy of higher values and an increased tax rate.

But there’s no need to jack up the rate. Throw in all the other houses in the city, the commercial property that rose and the new construction, and you’ll see that Orlando can collect $20.3 million more in the coming tax year without raising the rate. Whoo-hoo! More money for government to spend! Laissez les bon temps rouler!

Coincidentally — columnists can make this happen — the value of all the property in Orlando actually did go up 12.34 percent between this year and last — and it went up all over Central Florida, though typically not by quite that much. In Lake County, the tax zipped higher by 7.92 percent, in Seminole by 7.5 percent and in Osceola by 7.19 percent. Orange County, however, took the grand prize: the combined value of all its property rose by 8.3 percent. (The property appraiser attributed the increase to 6,000 new singlefamily homes.)

Oh, those government city piggies squeal like crazy when you cut back their slop . ... They can’t be trusted to evaluate their needs versus their wants in the real world.

You can almost hear governments around Central Florida dialing the caterers for the celebration. They can collect millions more, all while telling residents the lie that their taxes aren’t going up. What they mean is that the rate isn’t going up. More taxes certainly are being collected.

Remember that keeping the current tax rate actually results in more money for governments in years when the value of the tax roll rises. Ponder whether yours really needs the extra money. If not, push for what’s called the “rollback rate”— the rate at which the government collects the same amount of money as this year.

Unfortunately, it’s on you, dear reader, to tighten the reins on the 30 cities, 20 constitutional officers, four school boards, a couple water districts and an unfathomable number of special districts in Orange, Osceola, Seminole and Lake counties.

Here’s an example of why you can’t trust government:

A decade ago in the property boom, Lake County commissioners were trying desperately to make their budget for fiscal year 2008 balance. All summer long, they whined about how the Legislature was skimming from the top. Clermont’s manager discussed cutting services with his council and Leesburg’s presented ideas to “survive.”

Hahaha. That was the year that the County Commission alone collected $26.5 million more in property taxes than the previous year, a 32 percent increase. Yes, a mere 32 percent — just like the raise you got in your paycheck, right?

Oh, those government city piggies squeal like crazy when you cut back their slop. And they squeal when you throw in more. They can’t be trusted to evaluate their needs versus their wants in the real world.

This year is the start of a markedly upward trend again — count on values rising again next year — and it’s on taxpayers to keep government porkers from getting so obese that they might be considered ... well … hogs.

We all know what happens to them, don’t we? That’s right. Eventually, they’re bacon.