Voyage Expenses. – Luna Pool collaborative arrangement. Voyage expenses – Luna Pool collaborative arrangement, which was our other Luna Pool participants share of our revenue, was $5.4 million for the three months ended June 30, 2021 compared to $3.0 million for the three months ended June 30, 2020. The Luna Pool became operational during the quarter ended June 30, 2020, and this $2.4 million increase was due to having all fourteen vessels in the Luna Pool for the quarter ended June 30, 2021, compared to an average of 10 vessels for the quarter ended June 30, 2020, as well as improved utilization and time charter rates for the Luna Pool vessels for the three months ended June 30, 2021, compared to the three months ended June 30, 2020.
Vessel Operating Expenses. Vessel operating expenses increased by 8.8% to $28.8 million for the three months ended June 30, 2021, from $26.5 million for the three months ended June 30, 2020. Average daily vessel operating expenses increased by $675 per vessel per day, or 8.8%, to $8,336 per vessel per day for the three months ended June 30, 2021, compared to $7,661 per vessel per day for the three months ended June 30, 2020. This was primarily due to a general reduction in vessel operating expenses across the fleet in the three months ended June 30, 2020, as a result of COVID-19, which resulted in operating costs being deferred to subsequent quarters.
Depreciation and Amortization. Depreciation and amortization expense increased by 0.4% to $19.2 million for the three months ended June 30, 2021, from $19.2 million for the three months ended June 30, 2020. Depreciation and amortization expense included amortization of capitalized drydocking costs of $2.1 million and $2.0 million for the three months ended June 30, 2021, and 2020 respectively.
General and Administrative Costs. General and administrative costs increased by $1.8 million or 39.2% to $6.3 million for the three months ended June 30, 2021, from $4.5 million for the three months ended June 30, 2020. The increase in general and administrative costs was primarily as a result of a gain on a revaluation of an Indonesian Rupiah bank account last year, for the three months ended June 30, 2020, as well as an increase of $0.4 million on D&O insurances for the three months ended June 30, 2021.
Other Income. Other income was $0.1 million for both the three months ended June 30, 2021, and June 30, 2020, and consists of management fees for commercial and administrative activities performed by the Company for the Luna Pool.
Non-operating Results
Foreign Currency Exchange Loss on Senior Secured Bonds. Exchange gains and losses relate to non-cash movements on our 600 million Norwegian Kroner 2018 Bonds which are translated to U.S. Dollar at the prevailing exchange rate as of June 30, 2021. The foreign currency exchange gain of $0.3 million for the three months ended June 30, 2021, was as a result of the Norwegian Kroner weakening against the U.S. dollar, being NOK 8.6 to USD 1.0 as of June 30, 2021, compared to NOK 8.5 to USD 1.0 as of March 31, 2021. The foreign currency exchange loss of $4.9 million for the three months ended June 30, 2020, was as a result of the Norwegian Kroner strengthening against the U.S. dollar, being NOK 9.7 to USD 1.0 as of June 30, 2020, compared to NOK 10.5 to USD 1.0 as of March 31, 2020.
Unrealized Gain on Non-designated Derivative Instruments. The unrealized loss on non-designated derivative instruments of $0.3 million for the three months ended June 30, 2021, relates to the fair value movement in our cross-currency interest rate swap and is primarily due to the weakening of the Norwegian Kroner against the U.S. dollar. The unrealized gain on this swap for the three months ended June 30, 2020, was $6.4 million.
Interest Expense. Interest expense decreased by $2.5 million, or 22.3%, to $8.6 million for the three months ended June 30, 2021, from $11.1 million for the three months ended June 30, 2020. This is primarily as a result of a reduction in 3-month US LIBOR interest rates.
Income Taxes. Income taxes related to taxes on our subsidiaries incorporated in the United Kingdom, Poland and Singapore and our consolidated variable interest entity (“VIE”), incorporated in Malta. For the three months ended June 30, 2021, we had a tax charge of $190,000 compared to taxes of $168,000 for the three months ended June 30, 2020.
Share of result of equity accounted joint venture. The share of result of the Company’s 50% ownership in the Export Terminal Joint Venture was a gain of $2.0 million for the three months ended June 30, 2021, primarily as a result of increased volumes through the Marine Export Terminal, compared to a loss of $0.2 million for the three months ended June 30, 2020, as a result of initial startup volumes following the operational commencement of the Marine Export Terminal in January 2020.
Non-Controlling Interest. We have entered into a sale and leaseback arrangement with a wholly-owned special purpose vehicle (“lessor SPV”) of a financial institution. While we do not hold any equity investments in this lessor SPV, we have determined that we are the primary beneficiary of this entity and accordingly, we are required to consolidate this VIE into our financial results. Thus, the income attributable to the financial institution of $0.4 million is presented as the non-controlling interest in our financial results.
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