Sandeep Reddy
Executive Vice President and Chief Financial Officer at Domino's Pizza
Thank you, Russell, and good morning to everyone on the call. I'll begin with updates on our actions to drive the long-term profitability of Domino's and our franchisees.
First, pricing. During the second quarter, the average price increase across our U.S. system was 3.9%. We expect average pricing to be similar in the third quarter before moderating in the fourth quarter to approximately 2%, when we lap the carryout Mix & Match pricing change from October 2022.
Second, cost efficiencies as we continue to drive margin recovery. We drove improvement in our operating income margin, which grew by 240 basis points versus Q2 2022. This was despite foreign exchange rates having a 15 basis points negative year-over-year impact on operating income margin during the quarter. We now expect full year operating income margins in 2023 to reach or exceed 2019 levels.
Third, positive same-store sales growth excluding foreign currency impact in our U.S. and international businesses for the third consecutive quarter drove operating income improvement.
Now for our financial results for the quarter. Excluding the negative impact of foreign currency, global retail sales grew 5.8% due to positive sales comps and global net store growth. U.S. retail sales increased 1.7%. International retail sales excluding the negative impact of currency grew 10.1%. During Q2, same-store sales for the U.S. business increased 0.1%. The increase in U.S. same-store sales was driven by a higher average ticket, including the pricing actions I mentioned earlier, partially offset by order count declines.
Our carryout business remained strong in Q2, with same-store sales plus 5.6%, rolling over a plus 14.6% performance in 2022. The U.S. delivery business continues to be challenged. Q2 delivery same-store sales declined 3.5%, rolling over a minus 11.7% in Q2 2022. We expect Q3 same-store sales trends in our delivery business to be challenged similar to Q2. However, we expect a slight improvement in trends in Q4 as our updated loyalty program begins to roll out, followed by a considerable improvement in 2024 as a result of transaction growth from our Uber Eats partnership and other initiatives Russell has shared with you.
Shifting to unit count. We added 27 net new stores in the U.S. with 30 store openings and three closures, bringing our U.S. system store count to 6,735 stores at the end of the quarter, and our four-quarter net store growth rate in the U.S. to 1.8%. Domino's unit economics remained strong with continued EBITDA growth for our U.S. franchisees. We are on track to deliver average U.S. franchise store profitability of at least $150,000 in 2023.
Moving to international. Same-store sales in our international business excluding currency impact increased 3.6%. Our international store count increased by 170 net new stores comprised of 223 store openings and 53 closures. Closures were driven by the closure of the Denmark market, closures in Brazil as our master franchisee there continues to optimize its store base, and some closures in Russia where the master franchisee has indicated an intention to exit the market.
Domino's Pizza Enterprise, one of our publicly-traded master franchisees recently disclosed their intention to close an additional 65 to 70 underperforming stores. This will likely occur during our third quarter. These reductions in underperforming stores will pull down our net store growth rate in the upcoming quarter and for the full year. However, our new store builds in international continued to be robust and we anticipate returning to our full year run rate of net store growth in 2024 once these store closures are behind us.
Our additional 170 net stores brought the current trailing four-quarter net store growth rate in international to 6.3%. When combined with our U.S. store growth, the trailing four-quarter global net store growth rate was 4.7%. We now expect our 2023 global retail sales growth to track between the low-end and midpoint of our two to three-year outlook of 4% to 8%, driven by stronger international same-store sales. And we continue to expect our 2023 global unit growth to track to the low end of our 5% to 7%, two to three-year outlook.
Despite strong gross openings, we will be pressured by international store closures this year. Since these closures will be underperforming stores in certain challenged markets, this is not anticipated to materially impact the financial benefit of our new international store openings. Finally, a capital structure update. A debt leverage ratio of 4 times to 6 times is the appropriate leverage for our company and moves within the range depending on the level of interest rates. We have operated with this range of leverage for almost 20 years. In today's interest rate environment, you should expect us to use our free cash flow to make investments to grow the business, create strong shareholder returns through our dividend and share repurchase strategies and retire debt when it's in the best interest of our shareholders for us to do so. As always, we will be opportunistic if credit markets warrant additional borrowing or refinancing.
Thank you. We will now open the call to questions.