The increase in selling, general and administrative expenses as compared to the prior-year period was primarily a result of higher store payroll and store-related expenses associated with operating more stores, incentive-based compensation, marketing expenses, and legal expenses in the current year. As a percentage of net sales, SG&A increased by 100 basis points to 26.5% for the thirteen weeks ended September 28, 2024 from 25.5% for the thirteen weeks ended September 30, 2023, primarily as a result of higher incentive-based compensation, legal expenses, and marketing expenses in the current year, partially offset by lower store payroll expenses.
Income from operations. Income from operations increased $1.4 million, or 3.6%, to $40.0 million for the thirteen weeks ended September 28, 2024 from $38.6 million for the thirteen weeks ended September 30, 2023. The increase in income from operations was attributable to the factors noted above. As a percentage of net sales, income from operations was 9.4% and 10.3% for the thirteen weeks ended September 28, 2024 and September 30, 2023, respectively.
Interest expense. Interest expense was $0.4 million and $0.5 million for the thirteen weeks ended September 28, 2024 and September 30, 2023, respectively. The decrease in interest expense in the current-year period was primarily the result of a lower average debt balance in the current year.
Income tax expense. Income tax expense was $11.1 million for the thirteen weeks ended September 28, 2024 compared to $10.4 million for the thirteen weeks ended September 30, 2023. Our effective tax rate was 27.4% and 27.3% for the thirteen weeks ended September 28, 2024 and September 30, 2023, respectively. The tax rate for the thirteen weeks ended September 28, 2024 was consistent with the tax rate for the thirteen weeks ended September 30, 2023.
Net income. Net income was $29.4 million for the thirteen weeks ended September 28, 2024 compared to $27.7 million for the thirteen weeks ended September 30, 2023. The increase in net income was primarily attributable to the factors noted above.
Twenty-Six Weeks Ended September 28, 2024 Compared to Twenty-Six Weeks Ended September 30, 2023
Net sales. Net sales increased $91.0 million, or 12.0%, to $849.2 million for the twenty-six weeks ended September 28, 2024 from $758.2 million for the twenty-six weeks ended September 30, 2023. Consolidated same store sales increased 3.1%. Excluding the impact of the 8.4% increase in e-commerce same store sales, same store sales increased by 2.5%. The increase in net sales was the result of incremental sales from new stores and the increase in consolidated same store sales.
Gross profit. Gross profit increased $33.7 million, or 12.2%, to $309.6 million for the twenty-six weeks ended September 28, 2024 from $275.9 million for the twenty-six weeks ended September 30, 2023. As a percentage of net sales, gross profit increased by 10 basis points to 36.5% for the twenty-six weeks ended September 28, 2024 from 36.4% for the twenty-six weeks ended September 30, 2023. Gross profit increased primarily due to an increase in sales and merchandise margin, partially offset by the occupancy costs of new stores. The increase in gross profit rate of 10 basis points was driven primarily by an 80 basis-point increase in merchandise margin rate, partially offset by 70 basis points of deleverage in buying, occupancy and distribution center costs. The increase in merchandise margin rate was the result of supply chain efficiencies, while the deleverage in buying, occupancy and distribution center costs was driven primarily by the occupancy of new stores.
Selling, general and administrative expenses. SG&A expenses increased $28.3 million, or 14.8%, to $219.4 million for the twenty-six weeks ended September 28, 2024 from $191.1 million for the twenty-six weeks ended September 30, 2023. The increase in selling, general and administrative expenses as compared to the prior-year period was primarily a result of higher store payroll and store-related expenses associated with operating more stores, marketing expenses, and incentive-based compensation in the current year. As a percentage of net sales, SG&A increased by 60 basis points to 25.8% for the twenty-six weeks ended September 28, 2024 from 25.2% for the twenty-six weeks ended September 30, 2023, primarily as a result of higher incentive-based compensation and marketing expenses in the current year, partially offset by lower store payroll and store-related expenses.