In this article we will try to learn the method to create charts with confidence intervals.
Let us start with creating sample sales data for a week. Now let us create more data using stdev functions and it will show like as follows:
Let us calculate the differences (upper band and lower band) as follows:
Upper band formula : = B2+ B3
Lower band formula: = B2 - B3
Let us try to create the 2d chart as follows:
Now we have to change the chart type to an area graph:
It will look like this now:
To finish the chart, simply format the upper series with a light blue fill (to match the dark blue line) and the lower series to have a white fill.
Both the confidence bar chart and the confidence band chart are in the sample worksheet here. It depends upon how you prefer it to look like.