North America metropolitan area by population in North America: Greater Mexico City. Canada also breaks into the top ten largest metropolitan areas with the Toronto metropolitan area having six million people. The proximity of cities to each other on the Canada–United States border and Mexico–United States border has led to the rise of international metropolitan areas. These urban agglomerations are observed at their largest and most productive in Detroit–Windsor and San Diego–Tijuana and experience large commercial, economic, and cultural activity. The metropolitan areas are responsible for millions of dollars of trade dependent on international freight. In Detroit-Windsor the Border Transportation Partnership study
Leading sire in North America in 2015, earnings from Hong Kong and Japan are included on an adjusted basis. Leading sire in North America The list below shows the leading sire of Thoroughbred racehorses in North America for each year since 1830. This is determined by the amount of prize money won by the sire's progeny during the year. It is restricted to stallions which are based in North America, but currently includes earnings from overseas races in Great Britain, Ireland, France, Italy, Germany and the United Arab Emirates as well as domestic earnings. Prior to 2015, the Leading Sire Lists published by The Blood-Horse