I had $400 in foreign taxes in 2009 and $400 (lines 9) in 2010, but could only use $0 and $300 (lines 21) of them respectively. This year I have another $400 in foreign taxes (line 9), but my limitation (line
21) is $500, so I think I can carry $100 forward from 2009!Form 1116 Line 10 says "show computation". I can include the 2009 1116 showing the excess foreign tax and a letter explaining what I am doing, but what sort of computation do I need? Any help would be appreciated.