Estimate the number of tires purchased annually by a large car dealership in San Jose, California.

To estimate the number of tires purchased annually by a large car dealership in San Jose, California, we can use a top-down or bottom-up approach.

Top-Down Approach (Revenue-Based):

1. Estimate Annual Revenue: A large dealership might generate $100-200 million in annual revenue.
2. Estimate Tire Revenue Percentage: Tires (new sales, replacements, and service) could account for 5-10% of total revenue.
3. Calculate Annual Tire Revenue: $100M * 7.5% = $7.5 million.
4. Estimate Average Tire Cost: A set of four tires might cost $600-$1000 on average (including installation and markup).
5. Calculate Number of Tire Sets: $7.5M / $800 per set = 9,375 sets.
6. Calculate Total Tires: 9,375 sets * 4 tires/set = 37,500 tires.

Bottom-Up Approach (Service & Sales Volume-Based):

1. Estimate New Car Sales: A large dealership might sell 3,000-5,000 new cars annually. New cars come with tires, so this doesn't directly contribute to purchased replacement tires.
2. Estimate Used Car Sales: They might sell 2,000-4,000 used cars. A portion of these might require new tires upon sale (e.g., 20-30%).
   • Used cars needing tires: 3,000 * 25% = 750 cars.
   • Tires for used cars: 750 cars * 4 tires/car = 3,000 tires.
3. Estimate Service Department Tire Replacements: The service department handles routine maintenance and repairs.
   • Assume 50-100 cars serviced daily.
   • Assume 10-15% of service customers need tire replacements annually.
   • Cars serviced annually: 75 cars/day * 300 days/year = 22,500 cars.
   • Service customers needing tires: 22,500 * 12.5% = 2,812 customers.
   • Tires for service customers: 2,812 customers * 4 tires/customer = 11,248 tires.
4. Estimate Tire Sales from Tire Shop/Retail: Some dealerships have dedicated tire sales or promotions.
   • Assume an additional 500-1000 sets sold directly to customers.
   • Tires from direct sales: 750 sets * 4 tires/set = 3,000 tires.
5. Total Estimated Tires: 3,000 (used cars) + 11,248 (service) + 3,000 (direct sales) = 17,248 tires.

Reconciliation and Final Estimate: The top-down estimate (37,500 tires) is significantly higher than the bottom-up estimate (17,248 tires). This could be due to underestimating the service/retail portion or overestimating revenue allocation. A large dealership likely has a substantial service and parts department. Considering both approaches, a reasonable estimate would be in the range of 25,000 to 40,000 tires purchased annually, with a midpoint around 30,000 tires.