Operating income for the Other segment, exclusive of corporate and unallocated expenses, was $0.8 million for the three-months ended March 31, 2020, a decrease of approximately $0.1 million, or 12.8% lower than operating income of $0.9 million for the three-months ended March 31, 2019.
Interest and Other Income, net. Interest and other non-operating income, net, was $0.9 million for the three-months ended March 31, 2020, as compared to interest and other non-operating income, net, of $2.7 million for the three-months ended March 31, 2019. Foreign currency transaction losses were $2.9 million and $0.2 million for the three-months ended March 31, 2020 and 2019, respectively. Interest income was $4.5 million and $3.3 million for the three-months ended March 31, 2020 and 2019, respectively.
Provision for Income Taxes. Provision for income taxes was $87.0 million for the three-months ended March 31, 2020, an increase of $34.3 million, or 65.1% higher than the provision for income taxes of $52.7 million for the three-months ended March 31, 2019. The effective combined federal, state and foreign tax rate increased to 23.8% from 16.8% for the three-months ended March 31, 2020 and 2019, respectively. The increase in the effective tax rate was primarily attributable to a decrease in the equity compensation deduction.
Net Income. Net income was $278.8 million for the three-months ended March 31, 2020, an increase of $17.4 million, or 6.6% higher than net income of $261.5 million for the three-months ended March 31, 2019. The increase in net income was primarily due to the $63.7 million increase in gross profit. The increase in net income was partially offset by an increase in the provision for income taxes of $34.3 million and an increase in operating expenses of $10.1 million.
Non-GAAP Financial Measures
Gross Sales**. Gross sales were $1.24 billion for the three-months ended March 31, 2020, an increase of approximately $145.6 million, or 13.4% higher than gross sales of $1.09 billion for the three-months ended March 31, 2019. Net changes in foreign currency exchange rates had an unfavorable impact on gross sales of approximately $11.2 million for the three-months ended March 31, 2020.
Gross sales for the Monster Energy® Drinks segment were $1.16 billion for the three-months ended March 31, 2020, an increase of approximately $151.9 million, or 15.1% higher than gross sales of $1.01 billion for the three-months ended March 31, 2019. Gross sales for the Monster Energy® Drinks segment increased primarily due to increased worldwide sales by volume of our Monster Energy® brand energy drinks as a result of increased consumer demand as well as enhanced distribution and increased consumer demand for our Reign Total Body Fuel® high performance energy drinks. Net changes in foreign currency exchange rates had an unfavorable impact on gross sales for the Monster Energy® Drinks segment of approximately $10.8 million for the three-months ended March 31, 2020.
Gross sales of our Strategic Brands segment were $73.4 million for the three-months ended March 31, 2020, a decrease of $6.1 million, or 7.6% lower than gross sales of $79.5 million for the three-months ended March 31, 2019. Net changes in foreign currency exchange rates had an unfavorable impact on gross sales in the Strategic Brands segment of approximately $0.4 million for the three-months ended March 31, 2020.
Gross sales of our Other segment were $5.1 million for the three-months ended March 31, 2020, a decrease of $0.2 million, or 4.1% lower than gross sales of $5.3 million for the three-months ended March 31, 2019.
Promotional allowances, commissions and other expenses, as described in the footnote below, were $174.0 million for the three-months ended March 31, 2020, an increase of $29.5 million, or 20.4% higher than promotional allowances, commissions and other expenses of $144.4 million for the three-months ended March 31, 2019. Promotional allowances, commissions and other expenses as a percentage of gross sales increased to 14.1% from 13.2% for the three-months ended March 31, 2020 and 2019, respectively.
**Gross sales are used internally by management as an indicator of and to monitor operating performance, including sales performance of particular products, salesperson performance, product growth or declines and overall Company performance. The use of gross sales allows evaluation of sales performance before the effect of any promotional items, which can mask certain performance issues. We therefore believe that the presentation of gross sales provides a useful measure of our operating performance. The use of gross sales is not a measure that is recognized under GAAP and should not be considered as an alternative to net sales, which is determined in accordance with GAAP, and should not be used alone as an indicator of operating performance in place of net sales. Additionally, gross sales may not be comparable to similarly titled measures used by other companies, as gross sales has been defined