Nevertheless, it is key to provide some context or reference, even for small charts.
In SFE, I have always taken care to include reference in the different types of charts :
- Horizontal lines in BarChart and LineChart.
- Normality band in LineChart.
- Horizontal and Vertical lines in (unpublished yet) ScatterChart.
An additionnal reference can provide great help when it comes to read and analyse periodical data : background shading. To identify weekends in a week or every other month in a year for example.
The intensity of the shade must be carefully choosen, in order to be identified by the eye, but remaining neutral, without disturbing the reading of the the lines or columns.
Anyway, SFE now includes the possibility to create periodical vertical grey areas.
For this purpose, I added 3 additional parameters to Barchart and LineChart :
- ShadedStart : At which position the first grey band should start
- ShadedWidth : How many positions on the x axis should be shaded
- TransparentWhidth : How many positions should follow without shading.
- ShadedStart = -1. With ShadedStart = 0, the chart would have started with a grey zone covering Saturday + Sunday. -1 will have the chart to start with 1 position (sunday) on a grey background.
- ShadedWidth : 2. For Saturday + Sunday
- TransparentWhidth : 5. For the 5 working days of the week
As shown in the example above, the grey zone covers 100% of the cell's height, in order to display a continuous band when LineChart and BarChart are vertically aligned.
Robert Mundigl and Matt Grams provide an excellent example (again!) of Cross-tab chart with standard excel charts here.
PS : You might have noted that LineChart, BarChart and ScaleLine also provide a vertical reference line... that will be described in the next post.