Question: Until which year did this Polish professional boxer who lost to Joe Smith Jr. in 2016 in a knockout victory hold the IBO light heavyweight title?

Related documents: [0]  [DOC] Joe Smith Jr. (born September 20, 1989) is an American professional boxer who held the regional WBC International light heavyweight title from 2016 to 2017. He rose to prominence in 2016 by scoring an upset knockout victory over Andrzej Fonfara, and later becoming the first boxer to score a stoppage victory over former world champion Bernard Hopkins, who retired after their fight. [END] 
[1]  [DOC] Andrzej Fonfara (born 4 November 1987) is a Polish professional boxer who held the IBO light heavyweight title from 2012 to 2013. He currently resides in Chicago, the city with the third largest Polish population in the world behind Warsaw and New York City. [END]  
Answer: 2013
2013