Question: The French hairstylist Alain Pichon was well known as the hairdresser to a famous worldwide celebrity. In what year did this celebrity retire from his profession after a 20-year career?

Context paragraphs:
Oriana Fallaci: Oriana Fallaci (] ; 29 June 1929 – 15 September 2006) was an Italian journalist, author, and political interviewer.  A partisan during World War II, she had a long and successful journalistic career.  Fallaci became famous worldwide for her coverage of war and revolution, and her interviews with many world leaders during the 1960s, 1970s and 1980s.

David Beckham: David Robert Joseph Beckham, {'1': ", '2': ", '3': ", '4': "} ( ; born 2 May 1975) is an English former professional footballer.  He played for Manchester United, Preston North End, Real Madrid, Milan, LA Galaxy, Paris Saint-Germain, and the England national team for which he held the appearance record for an outfield player until 2016 when Wayne Rooney surpassed his total.  He is the first English player to win league titles in four countries: England, Spain, the United States and France.  He announced his retirement in May 2013 after a 20-year career, during which he won 19 major trophies.

Max Lincoln: Max Lincoln founded the British gay pornographic studio Eurocreme in 2002, in the same year that he directed and released "DreamBoy".  This first film gave its name to the line of productions that made Eurocreme famous worldwide for high-quality productions.  Lincoln has won numerous awards for his style of producing and directing.  The Eurocreme studio has released hundreds of titles, and has become a major player in the global gay porn industry.

Celebrity chef: A celebrity chef is a kitchen chef who has become famous and well known.  Today celebrity chefs often become celebrities by presenting cookery advice and demonstrations via mass media, especially television.  Several chefs have been credited with being the first celebrity chef, among them historically Bartolomeo Scappi and Marie-Antoine Carême.

Alain Pichon: Alain Pichon (born 19 April 1966) is a French hairstylist, and television personality.  His participation as a judge on the Hair TV Series made him a British household name in 2014.  The first series was broadcast in early 2014 on BBC Three, and achieved the highest viewing figures for the TV channel.  The show aired in Australia on the ABC2 channel later in 2014.  A second series is confirmed on BBC Two in 2015.  He is well known as the hairdresser to the worldwide celebrity David Beckham amongst many others.

L'École du micro d'argent: L'École du Micro d'Argent ("The School of the Silver Mic") is an album recorded by IAM.  The band became famous worldwide with this album, a classic in French hip-hop music.  It was partly recorded in the USA, with some aesthetic influences brought by RZA of the Wu-Tang Clan.

Thérèse Chardin: Thérèse Chardin is a French hairstylist who was a celebrity in the 1960s and 1970s.

Laurette Luez: Laurette Luez (born Loretta Mary Luiz; August 19, 1928 – September 12, 1999) was a supporting actress and successful commercial model who appeared in films and on television during a 20-year career.  She was a widely known Hollywood celebrity during the 1950s, owing much to publicity about her social life.  She is best known for her supporting role as photographic model Marla Rakubian in Rudolph Maté's 1950 film noir "D.O.A.".

Odile Gilbert: Odile Gilbert has been described as France's "most celebrated female hairstylist", and is the only woman in that profession to have received the French honor "Ordre des Arts et des Lettres".  Her career has been based in Paris and New York.

2016–17 Minnesota Timberwolves season: The 2016–17 Minnesota Timberwolves season was the 28th season of the franchise in the National Basketball Association (NBA).  On April 20, 2016, the Timberwolves hired Tom Thibodeau as their new head coach.  On September 23, 2016, Kevin Garnett would officially retire from the NBA, thus ending his 21-year career in the process.  On April 11, 2017, the Timberwolves would unveil a new logo and new uniforms to enter the next season.  They improved their 29–53 output from the previous season, but missed the playoffs for the 13th consecutive season, continuing the longest playoff drought in the NBA.

Supporting paragraphs: Alain Pichon David Beckham
Answer: 2013