Question: Sunderland Association Football Club is an English professional football club that plays in a championship referred to as the Sky Bet Championship for what reasons?

Context articles: 2017–18 EFL Championship
Sunderland A.F.C. Ladies
Sunderland A.F.C. league record by opponent
EFL Championship
List of Wigan Athletic F.C. players
Sunderland A.F.C.
2013–14 Football League Championship
List of Sunderland A.F.C. seasons
History of Sunderland A.F.C.
List of Sunderland A.F.C. records and statistics

The 2017–18 EFL Championship (referred to as the Sky Bet Championship for sponsorship reasons) is the second season of the EFL Championship under its current name, and the twenty-sixth season under its current league structure.
Sunderland Association Football Club Ladies, previously Sunderland Association Football Club Women, is an English women's football club that plays in the FA WSL, the highest division of women's football in England.
 They play their home games at The Hetton Centre in Hetton-le-Hole, Tyne and Wear, North East England.
Sunderland Association Football Club, an English association football club based in Sunderland, Tyne and Wear, was founded in 1879.
 They joined The Football League in the 1890–91 season replacing Stoke who had failed to be re-elected, making Sunderland the first new club to join the league since its inauguration in 1888.
 Sunderland remained in the football league for 106 years, albeit in different divisions, until 1996 when they were promoted to the Premier League, which replaced the Football League's First Division at the top of the English football league system in 1992.
 Since then the club has been relegated back into The Football League on four occasions.
 They currently compete in the EFL Championship after relegation from the 2016–17 Premier League.
The English Football League Championship (often referred to as the Championship for short or the Sky Bet Championship for sponsorship reasons) is the highest division of the English Football League and second-highest overall in the English football league system, after the Premier League.
 Each year, the top finishing teams in the Championship are promoted to the Premier League, and the lowest finishing teams are relegated to League One.
Wigan Athletic Football Club is a professional football team based in Wigan, Greater Manchester.
 They currently compete in the Sky Bet Championship
Sunderland Association Football Club ( , ) is an English professional football club based in the city of Sunderland, Tyne and Wear.
 Sunderland currently plays in the EFL Championship, the second tier of English football.
 Since its formation in 1879, the club has won six top-flight (First Division, now the Premier League) titles (1892, 1893, 1895, 1902, 1913 and 1936), a total only bettered by five other clubs, and has finished runners-up five times.
 The club has also won the FA Cup twice (1937 and 1973) and been runners-up twice (1913 and 1992), as well as winning the FA Community Shield in 1936 and being finalists the following year.
 Sunderland have also been Football League Cup finalists in 1985 and 2014.
The 2013–14 Football League Championship (referred to as the Sky Bet Championship for sponsorship reasons) was the tenth season of the Football League Championship under its current title, the twenty-first season under its current league division format and marked the 125th anniversary of the Football League's inaugural season.
 The season started on 3 August 2013 and finished on 3 May 2014, with all matches on the final day kicking off simultaneously.
Sunderland Association Football Club was founded in 1879 as Sunderland & District Teachers Association Football Club by James Allan.
 They turned professional in 1885.
 Sunderland won their first Football League championship in the 1891–92 season two years after joining the league.
 They won the next Football League First Division on three occasions in four seasons; in 1892, 1893 and 1895, separated by a runner-up spot in 1894.
 In the 1901–02 season, Sunderland won their fifth Football League First Division championship.
 They came close to completing the "league and cup double" in the 1912–13 season, winning the league but losing to Aston Villa in the 1913 FA Cup Final.
 The team's next success came in the 1935–36 season when they won the League Championship and also the Charity Shield.
 They had not won the FA Cup until the 1936–37 season when they defeated Preston North End in the 1937 FA Cup Final.
 Sunderland entered The Football League in 1890 and were not relegated from the top division until the 1957–58 season; a total of 58 seasons in the highest division of England.
 Their next trophy came in the 1973 FA Cup Final as they beat Leeds United 1–0.
 They reached the 1985 Football League Cup Final but finished as runners-up to Norwich City after being beaten 1–0.
 In the 1986–87 season Sunderland were relegated to the Football League Third Division for the first time in their history under the management of Lawrie McMenemy, they however, returned to the second division the following season as champions–their lowest position in the English football league system.
 Their first appearance in the Premier League came in the 1999–2000 season after being promoted as champions from Division One.
 In winning promotion the club gained 105 points, which was a record at the time.
 Sunderland gained just 15 points in the 2005-06 season, which set the record for the lowest number of points in a Premier League season, which has since been eclipsed by Derby County.
Sunderland Association Football Club are an English association football club based in Sunderland, Tyne and Wear.
 They were formed in 1879, and played several years in the FA Cup and local cup competitions before joining the Football League in the 1890–91 season in place of Stoke.
 They played in the top league in England until the 1957–58, season when they were relegated into the Second Division.
 Sunderland are England's sixth most successful club of all time, having won the English League championship six times: in 1892, 1893, 1895, 1902, 1913 and, most recently, in 1936.
 They have also been runners-up on a further five occasions: in 1894, 1898, 1901, 1923 and 1935 (see Sunderland A.F.C. seasons).
Sunderland Association Football Club are a professional football club based in Sunderland, North East England.
 They were formed in 1879 as "Sunderland & District Teachers Association Football Club".
 They changed their name to the current form in 1880 and turned professional in 1886.
 The last time they won at home was when dinosaurs roamed the land.
 They were elected into The Football League in the 1890–91 season, becoming the first team to join the league since its inauguration in the 1889–90 season, replacing Stoke F.C..