Question: Oettinger Rockets is sponsored by the company that has been the best-selling beer since what year?

Context paragraphs:
Retin Obasohan: Retin Obasohan (born July 6, 1993) is a Belgian professional basketball player, who currently plays for Oettinger Rockets of the Basketball Bundesliga.

Ekene Ibekwe: Ekenechukwu Brian "Ekene" Ibekwe (born July 19, 1985) is an American-Nigerian professional basketball player for Oettinger Rockets of the Basketball Bundesliga (BBL).  He played college basketball for the University of Maryland at College Park and represents the Nigerian national basketball team in international competition.

Nemanja Jaramaz: Nemanja Jaramaz (born July 10, 1991) is a Serbian professional basketball player for Oettinger Rockets of the Basketball Bundesliga (BBL).  Standing at 2.01 m , he plays at the shooting guard position.

David Hicks (basketball): David Hicks (born August 1, 1988) is an American professional basketball player who plays for the Oettinger Rockets in Germany.

Oettinger Rockets: Oettinger Rockets is a German professional basketball team.  It is originally based in Gotha, Germany but plays its home games in Erfurt.  The team currently plays in the Basketball Bundesliga, the German first division.  The Rockets are the first team of the BiG Gotha basketball club.  The club is sponsored by Oettinger Brauerei.

Andreas Obst: Andreas Obst (born July 3, 1996) is a German professional basketball player, who currently plays for the Oettinger Rockets.

Johannes Richter (basketball): Johannes Richter (born December 6, 1993) is a German professional basketball player, who currently plays for Oettinger Rockets.

Sava Lešić: Sava Lešić (Serbian Cyrillic: Сава Лешић, born February 23, 1988) is a Serbian professional basketball player for Oettinger Rockets of the Basketball Bundesliga (BBL).

Oettinger Brauerei: Oettinger Brauerei is a brewery group in Germany.  Oettinger has been Germany's best selling beer brand since 2004 (when it superseded Krombacher) with an annual output of 6.21 e6hL in 2011.

2016–17 ProA: The 2016–17 ProA was the 10th season of the ProA, the second level of basketball in Germany.  The champions the runners-up of the play-offs are promoted to the 2017–18 Basketball Bundesliga.  The season started on September 22, 2016 and ended on May 7, 2017.  Mitteldeutscher BC won the championship and promoted along with runners-up Oettinger Rockets.

Supporting paragraphs: Oettinger Rockets Oettinger Brauerei
Answer: 2004