TCE Rate. The average TCE rate for our fleet was $21,546 per day for the six months ended June 30, 2022, an increase of $9,970 per day from $11,576 per day for the six months ended June 30, 2021. The increase in average TCE rate was the result of higher spot rates for the six months ended June 30, 2022 as compared to the six months ended June 30, 2021. TCE rates represent net revenues (or revenue less voyage expenses) divided by revenue days. Net revenue utilized to calculate TCE is determined on a discharge to discharge basis, which is different from how we record revenue under U.S. GAAP.
Vessel Operating Expenses. Vessel operating expenses were $32.5 million for the six months ended June 30, 2022, an increase of $2.9 million from $29.6 million for the six months ended June 30, 2021. This increase is due to the timing of vessel operating expenses between quarters. Vessel operating expenses, by their nature, are prone to fluctuations between periods. Average fleet operating expenses per day, including technical management fees, were $6,979 per vessel for the six months ended June 30, 2022, as compared to $6,369 per vessel for the six months ended June 30, 2021. This is a result of higher costs due to additional crew changes in the current year as well as an overall increase in costs due to inflation for the six months ended June 30, 2022 as compared to the six months ended June 30, 2021.
Charter Hire Costs. Total charter hire expenses were $4.5 million for the six months ended June 30, 2022 , an increase of $1.9 million from $2.6 million for the six months ended June 30, 2021. This increase is as a result of the Company currently having three vessels chartered in as at June 30, 2022 compared with one vessel chartered-in as at June 30, 2021. Total charter-hire expenses comprised of an operating expense component of $2.3 million and a vessel lease expense component of $2.2 million for the six months ended June 30, 2022.
Depreciation. Depreciation expense for the six months ended June 30, 2022 was $14.8 million, a decrease of $0.9 million from $15.7 million for the six months ended June 30, 2021. This decrease is a result of three vessels classified as held for sale in the second quarter of 2022, when we ceased depreciating them.
Amortization of Deferred Drydock Expenditures. Amortization of deferred drydock expenditures for the six months ended June 30, 2022 was $2.2 million, a decrease of $0.6 million from $2.8 million for the six months ended June 30, 2021. The deferred costs of drydockings for a given vessel are amortized on a straight-line basis to the next scheduled drydocking of the vessel.
General and Administrative Expenses: Corporate. Corporate-related general and administrative expenses for the six months ended June 30, 2022 were $8.8 million, an increase of $0.4 million from $8.4 million for the six months ended June 30, 2021. The increase in costs was primarily due to an increase in travel related costs during the six months ended June 30, 2022 compared to the six months ended June 30, 2021.
General and Administrative Expenses: Commercial and Chartering. Commercial and chartering expenses for the six months ended June 30, 2022 were $1.9 million, an increase of $0.5 million from $1.4 million for the six months ended June 30, 2021. The increase in costs was primarily due to an increase in travel related costs during the six months ended June 30, 2022, compared to the six months ended June 30, 2021.
Interest Expense and Finance Costs. Interest expense and finance costs for the six months ended June 30, 2022 were $9.0 million, an increase of $0.9 million from $8.1 million for the six months ended June 30, 2021. Cash interest expense increased by $1.5 million to $8.2 million for the six months ended June 30, 2022, from $6.7 million for the six months ended June 30, 2021, primarily due to an increased average LIBOR and due to prepayment charges upon exercising the vessel purchase options for and prepayment of the related debt of the Ardmore Sealeader and Ardmore Sealifter during the six months ended June 30, 2022, as compared to the six months ended June 30, 2021. Amortization of deferred finance fees for the six months ended June 30, 2022 was $0.8 million, a decrease of $0.6 million from $1.4 million for the six months ended June 30, 2021.