Historically speaking, social security systems are a recent development. At the beginning of the twentieth century, there was limited state social intervention in the developed world, and even less in Latin America. A remarkable expansion of social rights took place in the second half of the century. By the 1970s most Latin American countries had set up at least some form of old-age protection, while others had already developed a wide welfare network. Public social expenditures grew to represent over 20 percent of the gross domestic product in a number of countries, including Argentina.