Fertility Rate: (Total Fertility Rate, or TFR), it is expressed as children per woman.It is calculated as the average number of children an average woman will have during her reproductive period (15 to 49 years old) based on the current fertility rates of every age group in the country, and assuming she is not subject to mortality.Migrants (net): The average annual number of immigrants minus the number of emigrants over the preceding five year period (running from July 1 to June 30 of the initial and final years), or subsequent five year period (for 2016 data).A negative number means that there are more emigrants than immigrants.The Congress consists of the Senate and the House of Representatives.
The United States of America is the fourth largest country in the world (after Russia, Canada, and China).
The population of the United States is about 250 million people.
What makes the USA the leader of the western world is its economical, political and military dominance over other countries. The Government is divided into three branches: legislative (the US Congress), executive (the President and his Administration) and judicial (the US Supreme Court).
The USA is the most powerful and highly developed country of the world.
The United States of America lies in the central part of North American continent. Its eastern coast is washed by the Atlantic Ocean and the Gulf of Mexico. They are the Hawaiian Islands, Alaska and the rest major part of the USA. The states differ very much in size, population and economical development.