For the second quarter in a row, state tax revenue going toward Honolulu’s financially challenged rail project did not hit the target laid out in an outdated financial plan.

The Honolulu Authority for Rapid Transportation reported this week that it received $55.1 million in general excise tax surcharge dollars for the third quarter of 2016 — about $4 million less than budget officials projected when they released their plan about four years ago.

During the previous quarter, rail received $56 million, which was $7 million less than projected.

Construction of the rail system relies on the Oahu-based surcharge funding. The project has received $1.8 billion in GET dollars, but the amount is about $48 million less than city officials had estimated under the 2012 plan, according to a HART release.

The 2012 plan assumed a 5 percent annual growth rate for the GET revenue. Rail officials came up with that growth rate using the average from GET data going back 30 years.

However, in December 2014 rail officials announced that the project was trending to receive $100 million less than they had anticipated. That contributed to the project’s first major budget crisis.

Nearly a year later, in October 2015, budget officials recommended that HART use a 4 percent growth rate to better reflect the GET collections since rail started and also account for the $100 million less in revenue.

“We feel pretty confident that 4 (percent) would be a better figure to base our income on,” HART budget analyst Michael McGrane told the agency’s board at the time. “It reflects good, actual data.”

The Honolulu rail project currently faces a budget gap of at least $1.8 billion, and project officials are working on a long-awaited update to the financial plan. They aim to have the new financial plan done by the end of this month, according to HART’s “interim plan” released in September.