The advantage of reverse-engineering a news story in this way is that good newspapers *should* cite the source of their underlying data.

In this case, the Guardian has a link to 'Get the Data' embedded in their article: http://www.guardian.co.uk/news/datablog/2011/jan/31/world-carbon-dioxide-emissions-country-data-co2#zoomed-picture

Go and take a look!

Some points to remember:

1) It's good practice to go to the source rather than simply using the direct download of the spreadsheet. You might well spot another useful data set, some extra metadata, or something else that gives you a better sense of the data's context.

2) Check the license!

3) Look carefully for metadata. Make a note of anything that seems significant.