Cost of operations. Cost of operations decreased $8.0 million, or 6%, to $127.9 million for the three months ended March 31, 2022 as compared to $135.8 million for the three months ended March 31, 2021 due to an $8.4 million decrease in cost of redemptions due to the decline in redemption revenue associated with our campaign-based loyalty programs within our BrandLoyalty segment.
General and administrative. General and administrative expenses increased $2.5 million, or 68%, to $6.2 million for the three months ended March 31, 2022 as compared to $3.7 million for the three months ended March 31, 2021, due to an increase in payroll and benefits expense, including stock compensation and other amounts associated with the Employee Matters Agreement as well as additional consulting expenses.
Depreciation and other amortization. Depreciation and other amortization increased $0.5 million, or 6%, to $9.1 million for the three months ended March 31, 2022 as compared to $8.6 million for the three months ended March 31, 2021 due in part to the acceleration of amortization associated with certain leasehold improvements.
Amortization of purchased intangibles. Amortization of purchased intangibles decreased $0.2 million, or 34%, to $0.3 million for the three months ended March 31, 2022, as compared to $0.4 million for the three months ended March 31, 2021, as a result of the decline in foreign currency exchange rates.
Interest expense (income), net. Total interest expense (income), net increased $9.1 million due the interest expense associated with our senior secured credit agreement entered in connection with the Separation in November 2021.
Taxes. Provision for income taxes decreased $7.6 million to $1.4 million for the three months ended March 31, 2022 from $9.0 million for the three months ended March 31, 2021 due to the decrease in earnings. The increase in the effective tax rate to 57.5% for the three months ended March 31, 2022 as compared to 32.0% in the prior year period was a result of increased U.S. corporate expenses, which we do not believe will be deductible.
Loss from investment in unconsolidated subsidiary – related party, net of tax. Loss from unconsolidated subsidiary – related party in 2021 represented our allocable share of the loss from our investment in our unconsolidated subsidiary, Comenity Canada, L.P., which was sold to an affiliate of our former Parent in August 2021.
Use of Non-GAAP financial measures
Adjusted EBITDA is a non-GAAP financial measure equal to net income, the most directly comparable financial measure based on accounting principles generally accepted in the United States of America, or GAAP, plus loss from investment in unconsolidated subsidiary – related party, provision for income taxes, interest expense (income), net, depreciation and other amortization, the amortization of purchased intangibles, and stock compensation expense. Adjusted EBITDA also excludes strategic transaction costs, which were comprised of amounts associated with the Employee Matters agreement entered into as part of the Separation. These items were not included in the measurement of segment adjusted EBITDA as the chief operating decision maker did not factor these expenses for purposes of assessing segment performance and decision making with respect to resource allocations.
We use adjusted EBITDA as an integral part of our internal reporting to measure the performance of our reportable segments and to evaluate the performance of our senior management, and we believe it provides useful information to our investors regarding our performance and overall results of operations. Adjusted EBITDA is considered an important indicator of the operational strength of our businesses. Adjusted EBITDA eliminates the uneven effect across all business segments of considerable amounts of non-cash depreciation of tangible assets and amortization of intangible assets, including certain intangible assets that were recognized in business combinations. A limitation of this measure, however, is that it does not reflect the periodic costs of certain capitalized tangible and intangible assets used in generating revenues in our businesses. Management evaluates the costs of such tangible and intangible assets, such as capital expenditures, investment spending and return on capital and therefore the effects are excluded from adjusted EBITDA. Adjusted EBITDA also eliminates the non-cash effect of stock compensation expense.
Adjusted EBITDA is not intended to be a performance measure that should be regarded as an alternative to, or more meaningful than, net income as an indicator of operating performance or to cash flows from operating activities as a