Question: The News Parade of the Year 1942 is documentary that included footage of a British statesman who led the Conservative Party for how many years?

Context paragraphs:
Later life of Winston Churchill: The later life of Winston Churchill documents the life of the British statesman from the end of World War II and his second term as Prime Minister of the United Kingdom, until his subsequent death and funeral in 1965.  After the end of the war Churchill had to step down as Prime Minister of the United Kingdom because the Conservative Party lost the 1945 election.  For six years he was to serve as the Leader of the Opposition.  During these years Churchill continued to influence world affairs; in 1946 he gave his Iron Curtain speech which spoke of the expansionist policies of the USSR and the creation of the Eastern Bloc; Churchill also argued strongly for British independence from the European Coal and Steel Community (which he saw as a Franco-German project as Britain still had an empire).  In the General Election of 1951 Labour was defeated and Churchill became Prime Minister for a second time.  Churchill continued to lead Britain but was to suffer increasingly from health problems.  Aware that he was slowing down both physically and mentally he resigned from the Cabinet in 1955.  However he continued to sit as an MP for Woodford until he retired from politics in 1964.  Churchill died on 24 January 1965 and was granted the honour of a state funeral.  He was buried in his family plot in St Martin's Church, Bladon near to where he was born at Blenheim Palace.

Robert Peel: Sir Robert Peel, 2nd Baronet, {'1': ", '2': ", '3': ", '4': "} (5 February 17882 July 1850) was a British statesman and member of the Conservative Party who served twice as Prime Minister of the United Kingdom (1834–1835 and 1841–1846) and twice as Home Secretary (1822–1827 and 1828–1830).  He is regarded as the father of modern British policing and as one of the founders of the modern Conservative Party.

Conservative Party (UK): The Conservative Party, officially the Conservative and Unionist Party, is a centre-right political party in the United Kingdom.  It is currently the governing party, having been so since the 2010 general election, where a coalition government with the Liberal Democrats was formed.  In 2015, the Conservatives led by David Cameron won a surprise majority and formed the first Conservative majority government since 1992.  However, the 2017 snap election on Thursday 8 June resulted in a hung parliament, and the Conservatives lost their parliamentary majority.  They are reliant on the support of a Northern Irish political party, the Democratic Unionist Party (DUP), in order to command a majority in the House of Commons through a confidence-and-supply deal.  The party leader, Theresa May, has served as both Leader of the Conservative Party and Prime Minister since 13 July 2016.  It is the largest party in local government with 9,237 councillors.  The Conservative Party is one of the two major contemporary political parties in the United Kingdom, the other being its modern rival, the Labour Party.  The Conservative Party's platform involves support for free market capitalism, free enterprise, fiscal conservatism, a strong national defence, deregulation, and restrictions on trade unions.

Castle Films: Castle Films (known as Universal 8 from 1977) was a home video distributor founded in California by former newsreel cameraman Eugene W. Castle (1897–1960) in 1924.  The company originally produced business and advertising films.  By 1931 it had moved its principal office to New York City.  In 1937, Castle branched out into 8 mm and 16 mm home movies, buying newsreel footage and old theatrical films for home use.  Castle's first home movie was a newsreel of the "Hindenburg" explosion.  That same year, Castle launched his "News Parade" series, a year-in-review newsreel; travelogues followed in 1938.  Castle also released sports films, animal adventures, and "old time" movies.

Mark Clarke (politician): Mark Clarke, born in June 1977, is a former UK Conservative Party parliamentary candidate that has been referred to as the "Tatler Tory", who is also former Director of the Young Britons' Foundation, former Chairman of Conservative Future, and ex-Director of the since-disbanded "Road Trip" electioneering organisation that bussed Conservative Party activists to marginal seats during the 2015 general election.  Clarke was suspended from the Party on 24 September 2015, following the suicide of Conservative activist Elliott Alston Raymond Johnson who had named Clarke as having bullied him.  A series of serious accusations subsequently appeared in several national newspapers about Clarke’s alleged misconduct and in November 2015 he was finally expelled and banned for life from representing or joining the Conservative Party again.  His alleged misconduct within the Conservative Party led to national newspaper coverage about the extent to which senior figures in the Party knew about complaints regarding his actions, coverage that subsequently led to the resignation of Grant Shapps, a government minister.

Winston Churchill: Sir Winston Leonard Spencer-Churchill, {'1': ", '2': ", '3': ", '4': "} (30 November 187424 January 1965) was a British statesman, army officer, and writer.  He served as Prime Minister of the United Kingdom from 1940 to 1945 and again from 1951 to 1955.  As a Member of Parliament (MP), he represented five constituencies over the course of his career.  As Prime Minister, Churchill led Britain to victory during World War II.  He led the Conservative Party for fifteen years from 1940 to 1955.

Benjamin Disraeli: Benjamin Disraeli, 1st Earl of Beaconsfield, (21 December 1804 – 19 April 1881) was a British statesman of the Conservative Party who twice served as Prime Minister of the United Kingdom, as well as a novelist.  He played a central role in the creation of the modern Conservative Party, defining its policies and its broad outreach.  Disraeli is remembered for his influential voice in world affairs, his political battles with the Liberal Party leader William Ewart Gladstone, and his one-nation conservatism or "Tory democracy".  He made the Conservatives the party most identified with the glory and power of the British Empire.  He is the only UK Prime Minister to have been of Jewish birth.

Edward Smith-Stanley, 14th Earl of Derby: Edward George Geoffrey Smith-Stanley, 14th Earl of Derby, (29 March 1799 – 23 October 1869) was a British statesman, three times Prime Minister of the United Kingdom, and to date the longest serving leader of the Conservative Party.  He was known before 1834 as Edward Stanley, and from 1834 to 1851 as Lord Stanley.  He is one of only four British Prime Ministers to have three or more separate periods in office.  However his ministries all lasted less than two years, and totalled 3 years 280 days.

The News Parade of the Year 1942: The News Parade of the Year 1942 is a 1942 9-minute documentary film made in the United States and directed by Eugene W. Castle.  It is composed of newsreel footage of wartime activity and includes footage of Joseph Stalin, Winston Churchill and others.

The New Canada: The New Canada is a Canadian political literature book written by Reform Party of Canada founder and leader Preston Manning and published by Macmillan Canada.  The book explains the personal, religious, and political life of Preston Manning and explains the roots and beliefs of the Reform Party.  At the time of its publishing in 1992, Reform had become a popular populist conservative party in Western Canada after the mainstream Progressive Conservative Party of Canada was collapsing in support and in 1991 decided to expand eastward into Ontario and the Maritimes.  One year later the PC party collapsed in the 1993 federal election, allowing the Reform Party to make political history in Canada, deplacing the PCs as the dominant conservative party in Canada.  Reform, later renamed the Canadian Alliance, merged with the PC Party in 2003, to form a united right-wing alternative to the governing Liberal Party of Canada, named the Conservative Party of Canada which has dropped many of the populist themes that the Reform Party had.

Supporting paragraphs: The News Parade of the Year 1942 Winston Churchill
Answer: fifteen