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On this example chess opening theory table, what does "Σ%" and the number before it mean?

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Did you maybe forget to paste a link? – sam hocevar May 14 '12 at 20:11
+1 @Sam Hocevar: Oops, I mean the internet ate the link, it's back now. Thanks! – blunders May 14 '12 at 20:50
up vote 2 down vote accepted

In the example given, the opening move was Nf3. A number of the main lines were given, eight more moves for Black, seven more moves for White. Then the percentages of games won by White (in tournaments) using the respective lines were tallied.

Here's a link to the table:

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Thank you for adding a better answer. Only thing that might improve it would be to take a screen grab of the table on Wiki, and crop the pic to show just the data you're referencing in your answer; doing so would make the answer easy to read, and insure if the table disappears/changes that you're answer still makes sense. Again, thank you! – blunders Feb 20 '13 at 2:23
@blunders: done. – Tom Au Feb 20 '13 at 22:37

The two figures in the “Σ%” column are the number of games referenced in the database (so “Σ” should be understood in its mathematical meaning, “total” or “sum”) and the percentage of games won by White.

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