The Woman Taken in Adultery is a painting of 1644 by Rembrandt, bought by the National Gallery, London in 1824, as one of their foundation batch of paintings. It is in oil on oak, and 83.8 x 65.4 cm.
In English-speaking culture, a milkman joke is a class of joke exploiting fear of adultery and mistaken paternity. This class of jokes has its roots in the early part of the 20th century, prior to the regular availability of milk in supermarkets. At that time, milk in glass bottles was delivered directly to customers' houses by milkmen, generally in the morning (at which time empty bottles were also collected). Men were commonly the main financial supporters of their families, and a man's wife tended to remain at home to care for their children and home. As the milkman would visit the home at a time when the husband would be away at work, this created an opportune situation for adultery.
Though Britain and the empire emerged victorious from the Second World War, the effects of the conflict were profound, both at home and abroad. Much of Europe, a continent that had dominated the world for several centuries, was in ruins, and host to the armies of the United States and the Soviet Union, who now held the balance of global power. Britain was left essentially bankrupt, with insolvency only averted in 1946 after the negotiation of a $US 4.33 billion loan (US$56 billion in 2012) from the United States, the last instalment of which was repaid in 2006. At the same time, anti-colonial movements were on the rise in the colonies of European nations. The situation was complicated further by the increasing Cold War rivalry of the United States and the Soviet Union. In principle, both nations were opposed to European colonialism. In practice, however, American anti-communism prevailed over anti-imperialism, and therefore the United States supported the continued existence of the British Empire to keep Communist expansion in check. The "wind of change" ultimately meant that the British Empire's days were numbered, and on the whole, Britain adopted a policy of peaceful disengagement from its colonies once stable, non-Communist governments were available to transfer power to. This was in contrast to other European powers such as France and Portugal, which waged costly and ultimately unsuccessful wars to keep their empires intact. Between 1945 and 1965, the number of people under British rule outside the UK itself fell from 700 million to five million, three million of whom were in Hong Kong.
A micro gallery was a computer-based guide to archives and museum collections, first developed for the collections at the National Gallery in London, UK It took three years to develop by the company Cognitive Applications, and opened in July 1991 as part of the facilities in the Sainsbury Wing. Visitors could use the system to determine which pictures they would like to see in the gallery. It was possible to print out personalised information for use during the visit. The Micro Gallery ran for 14 years and a CD-ROM with similar facilities was produced.

Question: How many people outside the country having the gallery displaying The Woman Taken in the main subject of milkman joke were under British rule in 1945?
Answer: 700 million