Spreadsheets in Finance and Forecasting Introduction to Charts, Summary Values and Pivot Tables

Objectives for Week 3 After studying this week’s work, you should be able to: present data in the form of graphs and charts using create data summaries using statistical measures Use pivot tables to create data summary tables Interpret the data correctly, drawing meaning from it Write coherent reports using data summary techniques

Charts A chart is any form of graphical representation of data In this case we are comparing the profits in millions of two companies

Cornershop Data As an example, of how we create charts we will look at the data we used in week 1

Action Point! Open up the Cornershop Collated Data Excel file now. Bring the first page to the screen. Follow the actions as we go through the slides.

Cornershop Data To begin with, we will graph the sales of Newspapers for Aughton

On the spreadsheet, select the area you wish to graph Then select the Chart Wizard icon The Chart Wizard dialogue box appears

select the chart type check the data range add title and axis labels put it on the same sheet or create an new sheet Finished!

The First Chart After creating your chart, you may not be totally happy with the way that it looks. You can change the chart in lots of different ways

Editing the Chart 1 Click on the outside of the chart, then on View, and select Toolbars, and select Chart The Chart toolbar appears. This will allow you to change some features of the chart

Challenges 1 Remove the Legend Add the data to the chart Change the chart into: A jagged line graph A pie chart A scatter graph of points 3-dimensional graph Change the title and the data labels.

Editing the Chart 2 Click on the edge of the chart, then on Chart, then Chart Options, and this box appears. This option box will allow you to change more features than on the toolbar.

Editing the Chart 3 Click on the edge of the chart, then on Chart, then Chart Type, and this box appears. This box supplies you with more chart types than you could possibly want. When you get bored with the ordinary types you can try some “custom types”

Challenges 2 Use the edit boxes from the previous two slides to change the chart. Firstly, explore the wide range of different charts that you can create. Secondly, experiment with different types of formatting; this should include different viewpoints for for 3-D charts different sized text different orientations of text different fonts and colours.

A More Complex Chart Highlight the whole block of data shown, and click Chart Wizard We will now plot the whole of the original Aughton data (not totals) Select Line graph as chart type, and add in title and axis labels

Comparing Data This is the chart that is produced. It is possible to create other charts for the same data

Alternative Presentation Although this is the same data the chart looks different, and is much harder to interpret

Interpreting the Chart Producing a chart is by no means the end of the story, in fact it’s just the beginning. Part of the art here is to produce charts which “tell a story” This means finding relationships in the data and selecting charts which express these most clearly.

Challenge 3 Note down three different features of this data that you can see immediately from the chart. Compare these with the person next to you. Do you think that what you have noticed would be of interest to the Area Sales Manager of Cornershop Ltd.? that is, to what extent do you think that these features might have explanations in real world events, rather than just random fluctuations?

Possible Interpretations For most of the week, the sales figures (least to greatest) are: Stationery, Confectionery, Newspapers and Grocery There does not seem to be much call for Stationery. On Sunday Newspapers outperform Groceries. There appears to be a bit of a dip in mid- week sales. This most affects grocery and confectionery

Summarising Data As well as creating charts, we can also use other features of Excel to summarise data Two important simple summary values are the Average and the Standard Deviation

Average and Standard Deviation On the Aughton Data Sheet, just below the Total, type in the row names “Average”, and below that “St.Dev.” In the “News” column, next to “Average”, type in : = Average(B4:B10) Underneath type in : = stdev(B4:B10)

Using Auto fill, create the following summary values for each column and row and for the two totals

What does the “average” value tell us? The average gives us a “representative” amount for that row or column If the average is substituted for each item, it gives the same total That is, £ on each day would have given £

What does the “Standard Deviation” value tell us? The standard deviation tells us about how varied the sales are from day to day Statistics tells us that we would normally* expect to similar data to be: less than the average + the standard deviation, greater than the average – the standard deviation * about 70% of the time

Commenting on the data In Aughton, the newspapers typically almost £300 worth a day. This ranges from £210 on Wednesday to £510 on Sunday. Looking at the data, we would not expect sales of Newspapers on a “normal” day to be much less than £200, or much higher than £300

Commenting on the data In Aughton, the newspapers typically sell almost £300 worth a day. This ranges from £210 on Wednesday to £510 on Sunday. Looking at the data, we would not expect sales of Newspapers on a “normal” day to be much less than £200, or much higher than £400 The average is £292.86, which is “about £300”. The standard deviation is £106.26, which is about £100. Average – St.dev = £ £ = £ Average + St.dev = £ £ = £399.12

Challenge 4 Examine the total Sales figures for Aughton Write a brief summary statement for this similar to the one we made for Newspapers

Challenge 4: Solution Each Day, the Aughton branch sells about £800 worth of goods. This ranges from a mid-week low of just under £600, to £1100 on Sunday. On a normal day, we would expect sales of somewhere between £600 and £1000.

Pivot Tables A Pivot Table is another important method of summarising data for example: This table is a pivot table created to total the information on sales for each day

The Raw Data Open the Spreadsheet Cornershop Raw Data This contains the same data that we have been working with, but in a raw, unformatted form. Check that you understand how this data has been presented.

Creating a Pivot Table Click on the button top left to select the whole sheet Click Data, then pivot table to action the Pivot Table Wizard.

The Pivot Table Options Drag the “Day” Button to here Drag the “Location” Button to here

The Pivot Table Options Drag the “Amount” Button to here Now click on anywhere in the body of the table then select this icon

Pivot Table Field Options This allows your data to be counted, totalled, averaged or a whole set of other things. Click on Sum, to create totals

Completed Pivot Table This has now created a pivot table which gives totals of your data for each location for each day. by dragging these labels in and out of the pivot table toolbar, we can create different pivot tables

Challenge 5 Create a pivot table to calculate the average amount of goods sold in each location

Pivot Table: Goods v Location This table has been reformatted to currency, as the calculations yielded several decimal places

Pivot Table Chart By clicking on chart in the Pivot Table Option box, you can present the data as a chart. Can you re- create this one?

Writing a Report An important feature of creating tables and charts, and calculating summary values is that they can be quickly understood by a busy manager. A presentation would normally take the form of a short report, word- processed with the tables and charts embedded in the text.