In 2019, the population of Spain officially reached 47 million people, as recorded by the ''Padrón municipal'' (Spain's Municipal Register). Spain's population density, at 91/km2 (235/sq mi), is lower than that of most Western European countries and its distribution across the country is very unequal. With the exception of the region surrounding the capital, Madrid, the most populated areas lie around the coast. The population of Spain has risen 2 1/2 times since 1900, when it stood at 18.6 million, principally due to the spectacular demographic boom in the 1960s and early 1970s.