Using the methodology of Council for Community and Economic Research (hereinafter, C2ER), a non-profit professional organization dedicated to research on community and economic development, the Institute of Statistics is responsible for collecting the prices of goods and services within the categories of supermarket, housing, transportation, public services and miscellaneous items. The data is sent to C2ER, who calculate the average prices and indices for each of the categories, allowing the comparison of costs with the equivalent cost in the United States. Finally, the Cost of Living Index (COLI) is calculated, which the C2ER has been preparing since 1968 for more than 300 urban areas in the United States and which Puerto Rico joined in the second quarter of 2014. The prices are published for users through a cost of living calculator, which makes it possible to compare the cost of living in Puerto Rico versus that of another city in the United States and vice versa. The Puerto Rico Cost of Living Index includes average prices three times a year for the following 56 product categories: ribeye steak, ground beef, sausage, fried chicken, canned tuna, whole milk, eggs, margarine, parmesan cheese, potatoes, guineos, lettuce, specialty bread, china juice, coffee, sugar, corn flake cereal, green peas, peaches, face towels, dishwashing detergent, extra virgin olive oil, frozen food, fresh corn, frozen whole corn, potatoes soft drinks, apartment rental, house price, energy total, landline, tire balancing, gasoline, visit to an optometrist, visit to a doctor, dental cleaning, ibuprofen, Lantus insulin, hamburger, pizza, fried chicken, men's cut, hair care for women (washing, drying and trimming), toothpaste, hair shampoo, dry cleaning for men's label, men's shirt, pants for boys, pants for women, washing machine, subscription to newspapers, movies, bowling, tennis balls, veterinary services, beer and wine.