In a previous article, "S Narayan" said:
I don't quite understand why you use this convention. Is it because it
simplifies the use in a spreadsheet?

I use it because CoPilot uses it, and that's the main customer of my data.
CoPilot undoubtedly uses it because it means that US and Canadian data is
positive.


--
Paul Tomblin http://xcski.com/blogs/pt/
Q: Why do PCs have a reset button on the front?
A: Because they are expected to run Microsoft operating systems.