In the 1920, many people's living conditions got better. There were improvements in public housing and new homes were built in many towns and cities. However, in 1929, the world entered the 'Great Depression' and some parts of the UK suffered mass unemployment. The effects of the depression of the 1930s were felt differently in different parts of the UK. The traditional heavy industries such as shipbuilding were badly affected but new industries-including the automobile and aviation industries-developed. As prices generally fell, those in work had more money to spend. Car ownership doubled from 1 million to 2 million between 1930 and 1039. In addition, many new houses were built. It was also a time of cultural blossoming, with writers such as Graham Greene and Evelyn Waugh prominent. The economist John Maynard Keynes published influential new theories of economics. The BBC started radio broadcasts in 1922 and began the world's first regular television service in 1936.