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For simplicity sake: Please can you explain to me what does this mean...."trade increases globally by 10%"?

assuming Country A = 100
assuming Country B = 100

does it mean....

1) 10% for each country so new trade means

 Country A = 110
 Country B = 110

or does it mean...

2) 5% for country A and 5% for country B, so new trade is

 Country A =  105
 Country B =  105   

Thank you for your time and effort in helping me with this question

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up vote 1 down vote accepted

It pretty much has to mean for each country. Otherwise, you get a different answer if you consider China and Taiwan two countries than you do if you consider them one country. And that wouldn't make any sense at all.

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I should not used the word Trade. I should have stated Sales Revenue. Will that make you think any different. thanks. – DiscoDude Nov 16 '11 at 19:33
No, that makes no difference. You can't say the company raised revenues by 100% across the board if each of 10 departments raised revenue 10%. (Also, you can't add percentages of different things anyway. 10% of an apple pie and 10% of a banana fritter isn't 20% of anything.) – David Schwartz Nov 16 '11 at 19:50
Thanks everyone, I am closing this off. – DiscoDude Nov 17 '11 at 10:46

It does not mean (2). It might mean (1), or it might mean simply that the total sales revenue for all countries combined rises by $10$%. In your example this could mean that Country A stays at $100$ while Country B rises to $120$. It could even mean that Country A drops to $90$ while Country B rises to $130$. Any combination of changes resulting in a total of $220$, $10$% more than the initial $200$, would count as a global increase of $10$% under this interpretation. In this case there can be variation from one country to another, but the overall sales revenue goes up by $10$%.

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I should not used the word Trade. I should have stated Sales Revenue. Will that make you think any different. thanks. – DiscoDude Nov 16 '11 at 19:33
@DiscoDude: No, that just makes the whole statement more intelligible. If I encountered the statement ‘in the wild’, I’d understand it to mean neither your (1) nor your (2), but my alternate interpretation. Your (1) is barely possible but very unlikely, and your (2) is right out. – Brian M. Scott Nov 16 '11 at 19:40
As you point out, the statement is ambiguous, but I think most people would go with your alternative of the total of all trade goes up by 10%. This could permit some countries to actually have trade decline, while total trade goes up by 10%. – TimothyAWiseman Nov 16 '11 at 19:42
@TimothyAWiseman - which one, the 5% for each country. thanks for looking at this. – DiscoDude Nov 16 '11 at 19:55
Actually, it is not true that on average each country's trade goes up by 10%. For example, consider two countries, one with a billion times the trade of the other. If thne larger country's trade goes up 10%, the smaller country's trade could do pretty much anything at all (go up 100%, go down 75%), it doesn't matter. The total will still go up 10%. – David Schwartz Nov 16 '11 at 20:09

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