Between 1950 and 2011, the world's urban population increased fivefold. In 2007, for the first time, the number of people living in cities surpassed the number of people living in the country. In 2019, the urban population had already reached 55% of the total population, and by 2050, it is estimated that just over two thirds of the population will live in urban areas. However, this growth is not constant in all parts of the world: according to the UN World Urbanization Prospects 2018 Report, the global urban population is expected to grow by 2.5 billion inhabitants between 2018 and 2050, with almost 90% of this increase concentrated in Asia and Africa. As populations in these areas increase, so will the demand for energy, food, and water, making resources more scarce. This scarcity will be compounded by the negative impact of urbanization on the climate and the environment.
Moreover, per the highlights of the 2019 report, in 2018, for the first time in history, the number of people aged 65 and over exceeded that of children aged under five. Projections indicate that by 2050, there will be more than twice as many people over 65 as children under five or young people between 15 and 24.