While I was writing the article about “Control charts”, I found out about “The Seven Basic Tools of Quality”. It was the first time I learned about that – and I realised that at least 4 of those seven tools can be built in Business Objects DeskI and WebI.
Those four tools are :
- A Control chart (described in a previous article)
- A Pareto chart
- A Histogram
- A Scatter Diagram
In this particular article, I wish to show you a Pareto Chart.
Basically, it is a chart that shows a bar and a line, where the line illustrates the importance of each of the bars.
This is accomplished by sorting the values from high to low and presenting them on a bar-chart. And then, adding the RunningSum/Total on a linechart.
The above chart shows that 50% of our reservations are made in 3 months April, August and February.
I realise that this isn’t the typical sort of data on which you use this particular chart, but I do believe this can be a useful way of presenting pretty much any kind of number. Where you want to compare your number to a % in total.
The example used on WikiPedia is various sources of absenteism. In an other source, I found the possible deseases among cattle, in order to find the deseases you want to tackle first.
So, enough talk. Without any further ado: The Pareto Chart.
Step 1. List your data in a table and sort it Large to Small :
Step 2 :
Calculate the Runningsum and divide by the total:
=RunningSum([Future guests])/Sum([Future guests]) in Report * 100
I multiply times 100 to make it a bit cleaner on the z-axis of the chart.
As soon as you do this however, any sorting on the table is gone, so we’ll have to re-sort.
Step 3: Click View structure, sort the measure you want to have sorted:
Second problem, the scale is wrong. It should be from 0 to 100. On the properties tab, make sure you set it to be 0 to 100. Given the type of number we have here, it will never be anything else than 0 to 100.
And we have ourselves a PARETO-chart.
Peter De Rop