segment also improved in the quarter, driven by lower inbound freight costs for our inventory, lower outbound shipping costs, due in part to growth in store fulfillment of e-commerce orders (buy online, pick up in store), and lower inventory shrinkage.
We classify certain warehousing, distribution, sourcing and other inventory procurement costs in selling and administrative expenses. Accordingly, our gross profit and selling and administrative expense rates, as a percentage of net sales, may not be comparable to other companies.
Selling and Administrative Expenses
Selling and administrative expenses increased $13.2 million, or 5.2%, to $266.3 million for the first quarter of 2024, compared to $253.1 million for the first quarter of 2023. The increase was driven by higher marketing expenses for certain brands, including Sam Edelman and Naturalizer, higher expenses associated with the expansion of our international business and higher information technology and consulting expense associated with the implementation of our cloud-based enterprise resource planning platform. As a percentage of net sales, selling and administrative expenses increased to 40.4% for the first quarter of 2024, from 38.2% for the first quarter of 2023.
Operating Earnings
Operating earnings decreased $6.8 million to $42.8 million for the first quarter of 2024, compared to $49.6 million for the first quarter of 2023, reflecting the factors described above. As a percentage of net sales, operating earnings were 6.5% for the first quarter of 2024, compared to 7.5% for the first quarter of 2023.
Interest Expense, Net
Interest expense, net decreased $1.8 million, or 32.8%, to $3.8 million for the first quarter of 2024, compared to $5.6 million for the first quarter of 2023. The decrease reflects lower average borrowings on the revolving credit facility, partially offset by higher weighted-average interest rates. The interest on our revolving credit facility is based on a variable rate, which adversely impacts our interest expense in the current elevated interest rate environment. While our interest expense for the remainder of 2024 will continue to be negatively impacted by the elevated interest rates, we expect to continue to reduce the borrowings under our revolving credit agreement to mitigate the impact of the high interest rate environment.
Other Income, Net
Other income, net decreased $0.5 million, or 33.5%, to $1.0 million for the first quarter of 2024, compared to $1.5 million for the first quarter of 2023, primarily attributable to higher amortization of the actuarial loss related to our pension plans. Refer to Note 12 of the condensed consolidated financial statements for further information. These decreases were partially offset by non-operating income associated with logistics services, which the Company began providing in the second half of 2023.
Income Tax Provision
Our effective tax rate can vary considerably from period to period, depending on a number of factors. Our consolidated effective tax rate was 23.0% for the first quarter of 2024, compared to 23.5% for the first quarter of 2023.
In 2021, the Organization for Economic Cooperation and Development (OECD) released Pillar Two Global Anti-Base Erosion model rules, designed to ensure large corporations are taxed at a minimum rate of 15% in all countries of operation. The OECD continues to release guidance and countries are implementing legislation to adopt the rules, which became effective on January 1, 2024. The United States has not yet enacted legislation implementing Pillar Two. We are continuing to evaluate the Pillar Two rules and their potential impact on future periods, but we do not expect the rules to have a material impact on our effective tax rate.
Net Earnings Attributable to Caleres, Inc.
Net earnings attributable to Caleres, Inc. was $30.9 million for the first quarter of 2024, compared to $34.7 million for the first quarter of 2023, as a result of the factors described above.