The increase in operating expenses was primarily due to increased selling and marketing expenses of $25.4 million, including sponsorship and endorsements and social and digital marketing, increased payroll expenses of $22.6 million, as well as increased distribution expenses of $18.1 million. Operating expenses as a percentage of net sales for the three-months ended March 31, 2024 were 25.5% as compared to 24.3% for the three-months ended March 31, 2023.
Operating Income
Operating income was $542.0 million for the three-months ended March 31, 2024, an increase of approximately $56.9 million, or 11.7% higher than operating income of $485.1 million for the three-months ended March 31, 2023. Operating income as a percentage of net sales decreased to 28.5% for the three-months ended March 31, 2024 from 28.6% for the three-months ended March 31, 2023. The increase in operating income was primarily the result of an increase in net sales, as well as an increase in gross profit as a percentage of net sales, partially offset by an increase in operating expenses.
Operating income was $138.0 million and $93.7 million for the three-months ended March 31, 2024 and 2023, respectively, for our operations in EMEA, Asia Pacific (including Oceania), Latin America and the Caribbean.
Operating income for the Monster Energy® Drinks segment, exclusive of corporate and unallocated expenses, was $628.1 million for the three-months ended March 31, 2024, an increase of approximately $67.3 million, or 12.0% higher than operating income of $560.8 million for the three-months ended March 31, 2023. The increase in operating income for the Monster Energy® Drinks segment was primarily the result of an increase in net sales as well as an increase in gross profit as a percentage of net sales.
Operating income for the Strategic Brands segment, exclusive of corporate and unallocated expenses, was $62.0 million for the three-months ended March 31, 2024, an increase of approximately $10.2 million, or 19.8% higher than operating income of $51.8 million for the three-months ended March 31, 2023. The increase in operating income for the Strategic Brands segment was primarily the result of an increase in net sales.
Operating loss for the Alcohol Brands segment, exclusive of corporate and unallocated expenses, was $6.0 million for the three-months ended March 31, 2024, a decrease of approximately $0.9 million, or 12.6% lower than operating loss of $6.9 million for the three-months ended March 31, 2023. The operating losses for the three-months ended March 31, 2024 were primarily due to continued expenses, infrastructure investments and the optimization of the Alcohol Brands segment.
Operating income for the Other segment, exclusive of corporate and unallocated expenses, was $1.0 million for the three-months ended March 31, 2024, as compared to operating loss of ($0.3) million for the three-months ended March 31, 2023. The operating income for the three-months ended March 31, 2024 was primarily the result of an increase in net sales.
Interest and Other Income, net
Interest and other non-operating income, net, was $35.8 million for the three-months ended March 31, 2024, as compared to interest and other non-operating income, net, of $12.5 million for the three-months ended March 31, 2023. Foreign currency transaction losses were $6.0 million and $11.2 million for the three-months ended March 31, 2024 and 2023, respectively. Interest income was $41.2 million and $23.5 million for the three-months ended March 31, 2024 and 2023, respectively.
Provision for Income Taxes
Provision for income taxes was $135.7 million for the three-months ended March 31, 2024, an increase of $35.6 million, or 35.5% higher than the provision for income taxes of $100.1 million for the three-months ended March 31, 2023. The effective combined federal, state and foreign tax rate increased to 23.5% from 20.1% for the three-months ended March 31, 2024 and 2023, respectively. The increase in the effective tax rate was primarily attributable to the decrease in the stock-based compensation deduction in the three-months ended March 31, 2024 as compared to the three-months ended March 31, 2023.
Net Income
Net income was $442.0 million for the three-months ended March 31, 2024, an increase of $44.6 million, or 11.2% higher than net income of $397.4 million for the three-months ended March 31, 2023. The increase in net income for the three-months ended March