## Introduction

If you have stumbled across this page hoping to find a cheap Business Class seat on Singapore Airlines (SIA), sorry! What you have arrived at is a page that explains how I found a superb result to my analysis of the last 19 years of SIA’s financial results.

## The Data

As I was using Power Query to help me to analyse SIA’s financial results, I downloaded their last 19 years’ worth of Annual Reports and Accounts and from there I downloaded everything you see here:

The question is, what can I do with all of that? What I often do as part of my financial analysis is to create a Net Income model. That is, I make Net Income the dependent variable and have one or more independent variables.

## The First Model

My first model comprises Y = Net Income  = All Other Variables in the above table, all six of them. I used the Data Analysis ToolPak for this and here is my output:

A Correlation Matrix of all variables and I have conditionally formatted the results to highlight the extreme values and the mid range values. For example, Revenue and Fuel Costs are very highly correlated as are Passengers and Rev Pax Km (Revenue Passenger Kilometers). Rather oddly, there is virtually no correlation between Staff Costs and the Number of Employees.

The Regression output are as follows:

Let’s note that the Adjusted R Squared value is high at 0.6755, the F statistic is significant at 7.25 but of the six independent variables only Staff Costs are significant, with a t statistic of 3.3287 and a P Value of 0.0060.

I think this is a superb result: Staff Costs being the only significant variable as its coefficient shows that a unit change to Staff Costs leads to a 2.5913 million SGD increase in Net Income.

The residuals plots show that everything is probably fine although we are only dealing with 19 data points or years of data:

## Conclusion

On the one hand, this model fails because only one variable is significant and using just Staff Costs to predict Net Income is not rational. This says that we need to refine or replace the model to find something better. That being true, why do I think I found something superb?

SIA is famous for its recruitment of and investment in high quality cabin crew and other members of staff. Whilst they don’t pay the highest salaries, they do reward well overall, training is high level and frequent, they use more cabin crew per flight than most, if not all, of its competitors to maximise customer satisfaction.

Out of all of that, the data contain the relationships that I just mentioned and regression analysis has brought them out! That is superb in my opinion!

I want you to replicate my work here so, whilst there is a spreadsheet to download, it only contains the data I have extracted and used. Feel free to ask for advice and guidance here but I am not providing the full spreadsheet file.

Duncan Williamson

14th August 2018

## Multi worksheet scenario model

### 25 10 2016

Tuesday 25th October

This is on its way … as promised … I will upload it later today or early tomorrow.

Duncan Williamson

## Can I automate the functions found in the ‘analysis ToolPak’ in Microsoft Excel?

### 22 09 2016

Someone asked this question in Quora and here is my answer which I think many of you will find useful:

If you use Excel on a Mac the chances are that you are not running Excel 2016 for the Mac and that your Mac does not have the ToolPak at all … I know, older versions have it and I know you can get alternatives!

In that case, I often demonstrate to Mac users how to create and automate the functions in the ToolPak: correlation matrix, regression analysis, moving averages, descriptive statistics … the others as well!

Descriptive statistics, for example, could be, for data in column A:

=AVERAGE(A:A)

=STDEV(A:A)

=KURT(A:A) …

=SKEW(A:A)

and so on.

Other answers have mentioned statistics software packages and that’s fine except they might not be free! Yes, if you are a student, your college or university is likely to have statistics software free for you to use.

How about R and R Studio, however? Open source, free, with massive amounts of support? Of course, it takes time to learn R but here is the code for some descriptive statistics using the psych package in R:

describe(order_sales_profit\$Sales)

That’s it! This is what I get from my current data set, sales values: not exactly the same as the ToolPak but my point is, it is very easy to replicate. Look at the screenshot of the output from R.

By the way, as a novice or beginner level user of Excel, there is a lot to learn from manually automating what’s in the ToolPak. Moreover, if you take my next learning point, use this opportunity to set up templates for you to analyse your data sets: that means, you automate the ToolPak elements once and that is it!

Finally, many elements of the ToolPak return non volatile results which means that if you change your data, you have to run the ToolPak again. If you automate it yourself, the formulas you create will all be volatile: change the data, change the answers!

Duncan Williamson

## I like such photographs

### 09 09 2016

I hope you can see this photo.

DW

## Top Tips: rules you really should follow

### 20 08 2016

19th August 2016

I have just completed another very successful Financial Modelling course and as you know, at the end of such courses, I come here and offer something new: a new topic, a new file or some advice. In this case, it is advice: things that you really need to think about when you create and work on any Excel file.

• Tab/Sheet Names
• Dead Cells 125,433 rows created but only 831 needed/active … files that balloon to many Mb for no real reason

Ever seen a tab name like this: FBU or OPT? I bet you have: short and sweet and probably mnemonic so easy to read and remember. How about L_P_Obasange_receivables_dont_forget_to PRINT_it_out? You think I am joking? I am serious! Just imagine you are working on your file with the large tab name and you want to link to a cell on that tab from another one: this is what will appear in your formula, by way of an example … =IFERROR(AND(A15=45,D26=”Jack”,L_P_Obasange_receivables_dont_forget_to PRINT_it_out!BA154 …

I am sure you see the point now. Keep tab names short and simple! More than that, if you do feel the need to use tabs to give instructions, colour code them to pass such messages: there are many colours to choose from so do that. Have a table of contents too. Give everyone a chance for a simple life!

If you share a file with someone, make sure any links in your file are either live or delete them. If you receive a file with links that you cannot use or update, you know how frustrating it is. Think of the user before you send linked files.

It is the easiest thing in the world to create a worksheet and as you work and improve what you are doing, to delete cells and ranges. We all do that. We create new ranges too, don’t we! Check your work now and again though and if these happen, take a break and check your file:

• it takes 30 seconds 45 seconds or even longer for the file to open
• what seems like a small file in terms of content and complexity has ballooned in size to 20 or 30 or more Mb
• saving the file takes an age too

If these things happen, go to a worksheet and press Ctrl+End and see where that takes you. You work only in the range A1: CD831 but Ctrl+End has taken you to CG125433 … what? How did that happen?

Even if there are not as many as an additional 1.8 million cells but just 500,000, look in those cells for formulas  that are trying to find something from somewhere that is not there … in some of these extra cells for example. Delete all of these extra cells. I did that this week: an extra 1.8 million cells in TWO separate worksheets complete with formulas. File size down from 28 Mb to 0.8 Mb, opening time just seconds, recalculation time hardy noticeable.

They were just some of things to report on from this week. Otherwise, this group of delegates really enjoyed the work and their end of course presentations were interesting and showed that significant learning had taken place!

Duncan Williamson

### 30 03 2016

Are you interested in using BI? Do you already use it?

Did you know that BI is free to create?

I will be adding some BI resources here this week … but there are already some here! Take a look at Power Query and Power Pivot for a start.

Back soon and if there’s something you want me to write about, let me know.

Duncan Williamson

## Are you Following me?

### 07 03 2016

Time is just flying by and although I’ve got so many things to share time is against me.

In addition to this blog you might want to follow me on LinkedIn too … I don’t accept everyone there but if you tell me you subscribe to this blog I guarantee acceptance.

I am working in Dubai this week: presenting a three day course on Financial Modelling and Business Intelligence. Then a two day course on Budgeting and Cost Control.

With my courses you get a tool box of functions and techniques. You also get one to one time with me as I solve your problems … financial modelling etc! You take away all of my notes and PowerPoint slides as well as all of my fully worked Excel files.

I use real world data in my models and demonstrations. You get full explanations from me. I am also honest: if you ask me something I will give you the right answer, even if it means I have to do further research or ask a friend!

Find out where I am working and what I am doing and who knows, you might even join me one day. Invite me to speak where you are and maybe we can get together that way.

Duncan Williamson

## Oil Tanker Problem

### 06 09 2015

Introduction

Last night I was finishing off some work when I came across a problem on a help site: the problem had been posted in December 2014 and hadn’t been answered. I realise that 9 months is a long time but I wanted to understand the problem and see if I could provide a solution: I did both!

One of the difficulties with the problem as stated was that the questioner asked for a nested IF solution, He insisted. Other people tried to help him and he duly provided a mock up of his worksheet for us all. Again he talked about a nested IF statement solution and even provided one … that he freely admitted didn’t work.

The problem is this:

• there are two oil storage tanks and oil is first measured by means of a dip stick which is then used to estimate the amount of oil in the tanks
• the oil is stored for days at a time and each day new oil is added
• every now and again, though, the tanks are drained

He said that by taking the differences between opening and closing stocks for each day he can estimate the amount of oil added; and by adding together the results for the two tanks he gets overall additions for a day.

Good!

Then he says the problem comes when the tanks are drained … his calculation shows a negative result for dranage day!

I translated his graphic into a worksheet and here it is.

The question is: can you solve his problem?

This table starts in B7 and in L11 there is a formula: =E11-E10+H11-H10

That formula is then filled down to the end of the table, day 31 in cell L41

You can see the problem clearly in the second part of the table, day 27 , where they have drained the first tank overnight:

That’s it: I solved this problem … can you? Let me know and I will share my solution. If you ask, you must tell me what you did to try to solve it. No try, no get! 😉

Duncan Williamson