Honolulu’s rail project received significantly fewer state tax dollars than expected for the quarter that just ended, indicating the largest public works effort in state history continues to struggle to keep up with the projections that were used to help finance it.

For the quarter ending June 30, rail received $52.3 million in state general excise tax surcharge dollars to help build the island’s elevated transit project, initial Honolulu Authority for Rapid Transportation figures show. That’s $8.3 million less than the $60.7 million that rail’s financial plan had predicted the project would see.

The shortfall almost wipes out the promising gains made in the previous two quarters, when the project’s GET revenues came in more than $1 million and $9 million above what the financial plan projected, respectively. It continues a pattern of fluctuation that the project has seen from quarter to quarter, leaving rail officials generally confounded at what to expect.

State Department of Taxation officials have pointed to a lag in processing tax returns as a key reason for the swings. But HART officials say that still doesn’t fully explain why their revenues remain behind.

Last December, when rail leaders announced that the project faced as much as a $910 million shortfall, they cited a trend of lagging revenues as a key reason for the problem, along with rising construction costs in one of the most competitive markets in the U.S.

At that time, rail was about $41 million behind what it was supposed to have collected in GET revenues. The most recent updates put rail about $38.9 million behind.

To date the project has taken in more than $1.52 billion in GET revenues — after the state’s 10 percent administrative skim off the top — and is tracking about 1.2 percent below the projections established under rail’s financial plan, HART numbers show.

At Thursday’s HART board meeting, incoming Chairman Don Horner said he was irked by "stale" budget numbers and financial figures being used to drive the project.

"I’m a little frustrated, I’m the type of person that needs a plan in front of me," Horner said during his opening remarks as the new chair. He succeeded Ivan Lui-Kwan, who had completed his term. "We’ve overpromised and underdelivered, as we sit here today. We need to correct that," Horner said.

HART expects to release an updated financial plan sometime this fall. Despite the confusion over the revenue stream, HART Executive Director Dan Grabauskas said the plan will aim to offer a "more predictable" projection of what revenues to expect from quarter to quarter.