HONOLULU — With the totals swinging wildly up and down from quarter to quarter, officials overseeing the island’s rail tax revenues are confounded by the project’s revenue collection, the Honolulu Star-Advertiser reported.

Rail officials announced earlier this week that the Honolulu Authority for Rapid Transportation (HART) received $64.8 million from Oahu’s general excise tax surcharge to fund construction for the months of July, August and September — $8.3 million more than what was expected, based on the project’s financial plan.

For April, May and June, however, the tax revenues were exactly $8.3 million below what was projected in the financial plan. State Department of Taxation officials have pointed to a lag in processing tax returns as a key reason for the swings. HART officials, meanwhile, said they still don’t fully understand what’s causing the swings. For the full story, click here.