Other income increased to $24.5 million during the six months ended June 30, 2022 from $21.9 million for the same period in 2021. Other income during the six months ended June 30, 2022 consisted primarily of management fees, income from our hotel properties and other ancillary income from our land and development projects and operating properties. Other income during the six months ended June 30, 2021 consisted primarily of a mark-to-market gain on an equity investment, management fees, other ancillary income from our operating properties, land and development projects and loan portfolio, income from our hotel properties, lease termination fees and interest income on our cash.
Land development revenue and cost of sales—During the six months ended June 30, 2022, we sold land parcels and residential lots and units and recognized land development revenue of $39.3 million which had associated cost of sales of $38.6 million. During the six months ended June 30, 2021, we sold residential lots and units and recognized land development revenue of $64.6 million which had associated cost of sales of $60.1 million.
Costs and expenses—Interest expense decreased to $53.4 million during the six months ended June 30, 2022 from $57.5 million for the same period in 2021. Our weighted average cost of debt was 4.9% for the six months ended June 30, 2022 compared to 4.4% for the six months ended June 30, 2021. The average balance of our outstanding debt was $2.20 billion for the six months ended June 30, 2022 and $2.60 billion for the same period in 2021.
Real estate expense increased to $23.1 million during the six months ended June 30, 2022 from $20.0 million for the same period in 2021. The increase was primarily due to an increase in expenses at certain of our hotel operating properties that have increased operations from the prior year, which was partially offset by asset sales.
Depreciation and amortization decreased to $2.7 million during the six months ended June 30, 2022 from $4.0 million for the same period in 2021.
General and administrative expense includes payroll and related costs, performance-based compensation, public company costs and occupancy costs. We recognized a net recovery of general and administrative expenses of ($3.9) million during the three months ended June 30, 2022 versus $51.8 million of expense for the same period in 2021. The decrease in 2022 was due primarily to a $54.7 million decrease in performance-based compensation. Our primary forms of performance-based compensation are our iPIP Plans and our annual bonus pool (refer to Note 14 to the consolidated financial statements for more information on the iPIP Plans). In addition, illustrative examples of our iPIP Plans may be found in our 2021 definitive proxy statement which is publicly available on the SEC’s website.
The provision for loan losses was $22.7 million for the six months ended June 30, 2022 as compared to a recovery of loan losses of $5.8 million for the same period in 2021. The provision for loan losses for the six months ended June 30, 2022 resulted primarily from a $25.0 million provision on our held-to-maturity security, which is now recorded at its expected repayment proceeds. The recovery of loan losses for the six months ended June 30, 2021 resulted from the reversal of Expected Loss allowances on loans that repaid in full during the period and from an improving macroeconomic forecast on commercial real estate markets since December 31, 2020.
The provision for losses on net investment in leases for the six months ended June 30, 2022 resulted from the macroeconomic forecast on commercial real estate markets. The provision for losses on net investment in leases for the three months ended June 30, 2021 resulted from the acquisition of two Ground Leases in June 2021 (refer to Note 5 to the consolidated financial statements).
During the six months ended June 30, 2022, we recognized an impairment of $1.8 million on an operating property based on the expected cash flows to be received. During the six months ended June 30, 2021, we recorded an aggregate impairment of $0.3 million in connection with the sale of residential condominiums.
Other expense was $2.5 million during the six months ended June 30, 2022 and $0.5 million for the same period in 2021. The increase in other expenses for the six months ended June 30, 2022 was due primarily to legal costs.
Income from sales of real estate—During the six months ended June 30, 2022, we recorded $0.5 million of income from sales of real estate primarily from the sale of Ground Leases. During the six months ended June 30, 2021, we recorded $0.7 million of income from sales of real estate from the sale of residential condominiums.