J. Michael Hansen
Executive Vice President & Chief Financial Officer at Cintas
Thanks, Todd, and good morning. Our fiscal 2024 second quarter revenue was $2.3 billion compared to $2.1 billion last year. The organic revenue growth rate, adjusted for acquisitions and foreign currency exchange rate fluctuations, was 9%. Organic growth by business was 7.9% for Uniform Rental and Facility Services; 12.7% for First Aid and Safety Services; 17.8% for Fire Protection Services; and 4.7% for Uniform Direct Sale.
Gross margin for the second quarter of fiscal '24 was $1.14 billion compared to $1.02 billion last year, an increase of 11.6%. Gross margin as a percent of revenue was 48% for the second quarter of fiscal '24 compared to 47% last year, an increase of 100 basis points. Strong volume growth and continued operational efficiencies helped generate this strong gross margin. Gross margin percentage by business was 47.4% for Uniform Rental and Facility Services; 54.5% for First Aid and Safety Services; 48.6% for Fire Protection Services; and 40.9% for Uniform Direct Sale. Gross margin for the Uniform Rental and Facility Services segment increased 40 basis points from last year. We continue to leverage our strong revenue growth and extracting efficiencies out of the business in order to expand margins.
Our year-over-year improvements are no accident. Our Six Sigma and engineering teams have helped us create efficiencies in the plant that allow us to maximize the utilization of our equipment, labor and energy. Our Smart Truck technology allows us to improve our route efficiencies and provide density to our existing routes. While energy expenses comprised of gasoline, natural gas and electricity were a tailwind of 40 basis points from last year, please keep in mind that some of the energy benefit is the result of efficiencies just mentioned. As an example, our rental revenue grew organically at 7.9%, but we only added 1% to our route structure since last year.
Gross margin for the First Aid and Safety Services segment increased 400 basis points from last year. Our revenue growth is strong and value -- our value proposition continues to resonate in this segment. Health and safety of employees remains top-of-mind. Our mix of revenues continues to be healthy, including growing high margin recurring revenue products like AED rentals eyewash stations in Waterbury. We continue to use technology, like Smart Truck, to optimize our routes and improve efficiencies. And our first aid dedicated distribution center allows us to lower product costs. All of these contributes to our improved margins.
Selling and administrative expenses grew $64.4 million or 11.1% over last year. Strong revenue growth creates leverage, which allows us to invest in the business. We continue to invest in our people, adding selling resources, investing in our management training program to develop future leaders and expanding our talent acquisition efforts.
Operating income of $499.7 million compared to $444.9 million last year. Operating income as a percent of revenue was 21% in the second quarter of fiscal '24 compared to 20.5% in last year's second-quarter, an increase of 50 basis points. Our effective tax-rate for the second quarter was 20.9% compared to 22.1% last year. The tax-rates in both quarters were impacted by certain discrete items, primarily the tax accounting impact for stock-based compensation.
Net income for the second quarter was $374.6 million compared to $324.3 million last year. This year's second quarter diluted EPS of $3.61 compared to $3.12 last year, an increase of 15.7%.
Todd provided our annual financial guidance. Related to the guidance please note the following. Fiscal '24 interest expense is expected to be $100 million compared to $109.5 million in fiscal '23, predominantly as a result of less variable rate debt. Our fiscal '24 effective tax-rate is expected to be 21.3%. This compares to a rate of 20.4% in fiscal '23. The higher effective tax-rate negatively impacts fiscal '24 EPS guidance by about $0.16 and diluted EPS growth by about 120 basis points. Our financial guidance does not include the impact of any future share buybacks and guidance includes the impact of having one more workday in fiscal '23 compared to fiscal -- I'm sorry, fiscal '24 compared to fiscal '23. This extra workday comes in our fiscal third quarter.
I'll turn it back to Jared.