Apr. 5--Here's the deal about the most complicated thing on the April 7 city ballot.

It all started 25 years ago.

It's really important, because it will affect how much in property taxes the city can collect each year.

Supporters say it will cause property taxes to go down.

Opponents say it might cause property taxes to go up.

Understanding it takes you through a couple of wacky acronyms that sound like they fell out of a Walt Disney television show in 1959: MUSA. MESA.

WHAT IS IT?

Proposition 9 is a voter initiative about property taxes in Anchorage. The goal is to lower property taxes. The initiative aims to strengthen a tax cap originally passed by voters in 1983 and changed in 2003.

The tax cap limits how much the city can increase overall property taxes each year. Taxes can only increase from the amount collected the preceding year by a percentage that includes inflation and a five-year average of population change.

Proposition 9's supporters say the initiative would reduce the amount that property taxes could increase in the future. They say it would do that by adding to the mix payments to city government from city-owned utilities and city-owned businesses. Moving that money -- currently about $16.5 million a year -- under the tax cap would reduce the amount charged to home and business property owners, supporters say.

WHAT are UTILITY AND ENTERPRISE PAYMENTS?

City, state and federal governments don't pay property taxes.

But the state and federal governments do make what are called "payments in lieu of taxes" on government property inside the city.

City-owned utilities like the Anchorage Water & Wastewater Utility and Municipal Light & Power own "plant" -- utility equipment, lines, pipes and so on -- and the city collects "payments in lieu of taxes" on that.

The city also owns entities that do business, like the Port of Anchorage and Merrill Field. The city collects payments in lieu of taxes from them too.

The utility payments are called MUSA, which stands for Municipal Utility Service Assessments. The enterprise payments are called MESA -- Municipal Enterprise Service Assessments.

WHO SUPPORTS IT AND WHY?

The initiative is on the ballot because a group called the Municipal Taxpayers' League collected 13,000 signatures on petitions in little more than three weeks -- a very short time for such a drive. They needed about 7,000 signatures.

The Chamber of Commerce supports Proposition 9 too. The business group says having the utility payments as part of the tax cap would make the cap more effective and would stabilize changes in property taxes.