Nice: The German bank Comdirect is drawing graphical tables. Not so nice: The reference lines. They are wrong. Because they make some of the bars look like columns. I’ve corrected them. The way I did in my diagrammatic.
Source: Comdirect Informer showing stock quote data, 2011-08-09. Enlargement (center) and redesign (below): Me.
When do we need reference lines? When the eye needs to be guided. Columns and bars don’t normally need reference lines. Because a column is higher than it is wide. A bar is wider than it is high. Exception: Thin bars and flat columns. What to do then: Feet for columns, borders for bars. The bars at Comdirect have feet. The wrong way round.