For openings research the Reference search is one of the most important tools in ChessBase.

 

When you investigate opening variations the program makes available with its access via optimised search routines informative displays for the evaluation of various continuations. Even in searches in the early stages of the game, where of course extremely large numbers of games are collected and evaluated, the search function very quickly produces meaningful displays of information.

 

The Fashion Index plots the popularity of the current opening variation over time. This can show you how an opening evolved historically.

 

Below we have an example of a display for the Advance Variation of the French Defence. What is interesting here is the display of the Tab Popularity.

 

 

What is the significance of the values on both axes?

 

 

The horizontal axis represents the various years;  the values on the vertical axis are percentages. These refer to all the games which meet the search criteria.

 

In the example being displayed the user can see at once that the Advance Variation was frequently played towards the end of the 1890s.