Selling, general and administrative expenses
Selling, general and administrative (SG&A) expenses increased $111.2 million or 22.2%, to $612.1 million for the 13 weeks ended April 29, 2023, compared to $501.0 million for the 13 weeks ended April 30, 2022. SG&A expenses as a percentage of net sales increased to 23.2% for the 13 weeks ended April 29, 2023, compared to 21.4% for the 13 weeks ended April 30, 2022, primarily due to deleverage of store payroll and benefits, deleverage of corporate overhead due to strategic investments, and deleverage of marketing expenses, partially offset by leverage of incentive compensation and store expenses.
Pre-opening expenses
Pre-opening expenses were $0.7 million for the 13 weeks ended April 29, 2023 compared to $2.3 million for the 13 weeks ended April 30, 2022.
Interest (income) expense, net
Interest income, net was $7.3 million for the 13 weeks ended April 29, 2023 compared to interest expense, net of $0.4 million for the 13 weeks ended April 30, 2022, due to higher average interest rates and higher average cash balances during the quarter. We did not have any outstanding borrowings on the credit facility as of April 29, 2023 and April 30, 2022.
Income tax expense
Income tax expense of $102.4 million for the 13 weeks ended April 29, 2023 represents an effective tax rate of 22.8%, compared to $105.9 million of income tax expense representing an effective tax rate of 24.2% for the 13 weeks ended April 30, 2022. The lower effective tax rate is primarily due to benefits from income tax accounting for stock-based compensation.
Net income
Net income was $347.1 million for the 13 weeks ended April 29, 2023, compared to $331.4 million for the 13 weeks ended April 30, 2022. The increase in net income is primarily related to the $113.8 million increase in gross profit, the $7.7 million increase in interest income, net, and the $3.5 million decrease in income tax expense, partially offset by the $111.2 million increase in SG&A expenses.
Liquidity and capital resources
Our primary sources of liquidity are cash and cash equivalents, cash flows from operations, and borrowings under our credit facility. The most significant components of our working capital are merchandise inventories and cash and cash equivalents reduced by accounts payable, accrued liabilities and deferred revenue. As of April 29, 2023, January 28, 2023, and April 30, 2022, we had cash and cash equivalents of $636.4 million, $737.9 million, and $654.5 million, respectively.
Our primary cash needs are for rent, capital expenditures for new, remodeled, and relocated stores, increased merchandise inventories related to store expansion and new brand additions, supply chain improvements, share repurchases, and continued investment in our information technology systems.
Our most significant ongoing short-term cash requirements relate primarily to funding operations (including expenditures for lease expenses, inventory, labor, distribution, advertising and marketing, and tax liabilities) as well as periodic spend for capital expenditures, investments, and share repurchases. Our working capital needs are greatest from August through November each year as a result of our inventory build-up during this period for the approaching holiday season.
Long-term cash requirements primarily relate to funding lease expenses and other purchase commitments.