I have data on exports and imports for 60 or so countries. My data looks like this

Argentina Australia 123456 Argentina Australia 123456
Argentina Belgium 564789 Argentina Austria 123146
Argentina Brazil 879455 Argentina Belgium 1231458
Argentina Canada 456789 Argentina Brazil 2312365
Australia Australia 123456 Argentina Bulgaria 123456
Australia Belgium 564789 Argentina Canada 123146
Australia Brazil 879455 Australia Argentina 1231458
Australia Canada 456789 Australia Austria 2312365

What I need to do is subtract the first column of numbers from the second, but only when the first and second columns match the fourth and fifth. Unfortunately, because the columns 4-6 are longer than 1-3, I need to get Excel to look for the match within an array. What I am doing now is using vlookup to get excel to search, for example, for "Australia" in the second column and then return the value in the third column. However, at the moment, I need to manually specify the table array (because the word australia will reappear about 60 times). Is there a way to get excel to automatically do this for me?

Many thanks for any help.