Please read the following table in Markdown format and then answer the question according to the table. Table cells in one row are seperated by '|', and different rows are seperated by '
'.

Table:
| Year | Fighter | Nation represented | Sport | Sanctioning body or league | Weight class represented or contested |
| --- | --- | --- | --- | --- | --- |
| 2007.0 | Floyd Mayweather Jr | United States | Boxing | Not applicable | Welterweight |
| 2008.0 | Floyd Mayweather Jr | United States | Boxing | Not applicable | Welterweight Junior middleweight |
| 2009.0 | Manny Pacquiao | Philippines | Boxing | Not applicable | Super featherweight Lightweight Welterweight |
| 2010.0 | Floyd Mayweather Jr | United States | Boxing | Not applicable | Welterweight |
| 2011.0 | Manny Pacquiao | Philippines | Boxing | Not applicable | Welterweight |
| 2012.0 | Floyd Mayweather Jr | United States | Boxing | Not applicable | Welterweight |
Question:
Which nation won the boxing championship in 2012?
Answer:
United States