Tax collections needed to fund Honolulu's planned elevated commuter rail rose slightly to $13.6 million last month, based on figures released by the state Department of Taxation.

That's up from $13.2 million in November 2008 and in line with city expectations of about $13.7 million a month from the surcharge implemented in January 2007. Through the first five months of the fiscal year, transit tax collections are down about 4 percent to $65.6 million compared with the same period a year earlier.

Through the first five months of this fiscal year, collections are averaging about $13.1 million a month.

Tax collections have fallen amid declining visitor arrivals and rising unemployment. City officials have said that they expect lower transit tax collections to be offset by lower construction costs and a future economic rebound.

The city also plans to rely on increased federal funding — including diverting $305 million in federal money intended for TheBus — to help make up for the lower-than-anticipated tax revenue.

So far the tax has generated about $336 million, excluding a 10 percent administrative fee retained by the state.

City officials hope to begin construction of the $5.5 billion, 20-mile train system early next year.

Proposals to build a train system for Honolulu had been considered in the 1980s and 1990s, but never materialized. However, plans to build a train were kick-started after Mayor Mufi Hannemann took office in 2005.