“Start with a joke.” My boss used to say when I am nervous about an upcoming presentation. Although, I am not nervous to post this article, I think a joke will always help.
So here it goes:
[originally posted on 5th May 2008]
Now to more serious matters.
VLOOKUP (and other lookup formulas) are very powerful and quite practical. They can fetch you the information you are looking for from a heap of data.
Now that we have seen the power of VLOOKUP thru several posts this week, I want to test your understanding of these formulas by presenting 3 challenges.
Download the excel workbook with these challenges
Click here to download excel workbook with all the data for these challenges.
Challenge # 1: Price After Discount
We come across this problem quite often. You have a list of discount codes and applicable quantity thresholds. For eg. you may sell an item at $50, but if I buy more than 1 item, you will give a 10% discount. The discount goes up as I purchase more quantity.
Now, given a list of item quantities, how do you calculate the amount payable using lookup formulas? That is our first challenge.
Challenge # 2: Price after accumulated quantity discount
This is essentially same as above formula, but the discounts apply on accumulated quantities bought so far. For eg. I will get first item for 0% discount, 2nd and 3rd items for 10% discount, 4th item for 15% discount … 26th item for 50% discount etc.
Now, given a list of customer names and quantities they bought (in the same order), how do you calculate the amount payable for each transaction?
Challenge # 3: Closest price based on the quantity purchased
This is an interesting challenge. The price after discount is determined based on the quantity bought. For eg. the discount thresholds are 1, 3, 5, 10, 25 etc. Now, given a quantity of items bought, we determine the price by finding the closest threshold to it. So, a quantity of 7 will get the price from threshold 5 as against 10.
Few guidelines on solving these challenges:
Although the above problem might appear simple, the solution is not so straightforward.
- Use a variety of formulas: Do not just rely VLOOKUP. Instead experiment with formulas like SUMIF, COUNTIF, INDEX, MATCH etc. to get results
- Use helper columns: Break down the problem in to several steps and use helper columns to get the results
- Use pen & paper: Write down the logic first, then simulate it in excel using formulas. It clears your mind fast.
- Many solutions exist: Each problem can be solved in several different ways. So once you find a solution, feel free to explore other options
- Share your solutions: Use comments box to share your solutions with us. I am always looking for new ways to solve problems. So teach me…
Solution to the Challenges:
Here is a workbook with one set of solutions for the problems. As I said, many other solutions do exist. So use this workbook as an indication of what is possible.
Click here to download excel workbook with all the data for these challenges.
One Link to More VLOOKUP Awesomeness:
Debra at Contextures has chipped in with some interesting videos on VLOOKUP formulas. Check them out here.
The 2nd Joke:
It is quite difficult to set an expectation and then meet it. More so with jokes. But do you know that Chandoo.org’s 404 pages show Excel error messages? For example go to http://chandoo.org/wp/missing_file/. Refresh the page to see a different message. 🙂
It is Diwali (the festival of lights) in India this weekend. So I am going to spend time with family, light some fireworks and relax. I wish you a happy Diwali if you celebrate one. Even otherwise, I wish a lot of light and warmth in to your life this year.
13 Responses to “Using pivot tables to find out non performing customers”
To avoid the helper column and the macro, I would transpose the data into the format shown above (Name, Year, Sales). Now I can show more than one year, I can summarize - I can do many more things with it. ASAP Utilities (http://www.asap-utilities.com) has a new experimental feature that can easily transpose the table into the correct format. Much easier in my opinion.
David
Of course with alternative data structure, we can easily setup a slicer based solution so that everything works like clockwork with even less work.
David, I was just about to post the same!
In Contextures site, I remember there's a post on how to do that. Clearly, the way data is layed out on the very beginning is critical to get the best results, and even you may thinkg the original layout is the best way, it is clearly not. And that kind of mistakes are the ones I love ! because it teaches and trains you to avoid them, and how to think on the data structure the next time.
Eventually, you get to that place when you "see" the structure on the moment the client tells you the request, and then, you realized you had an ephiphany, that glorious moment when data is no longer a mistery to you!!!
Rgds,
Chandoo,
If the goal is to see the list of customers who have not business from yearX, I would change the helper column formula to :
=IF(selYear="all",sum(C4:M4),sum(offset(C4:M4,,selyear-2002,1,columns(C4:M4)-selyear+2002)))This formula will sum the sales from Selected Year to 2012.
JMarc
If you are already using a helper column and the combox box runs a macro after it changes, why not just adjust the macro and filter the source data?
Regards
I gotta say, it seems like you are giving 10 answers to 10 questions when your client REALLY wants to know is: "What is the last year "this" customer row had a non-zero Sales QTY?... You're missing the forest for the trees...
Change the helper column to:
=IFERROR(INDEX(tblSales[[#Headers],[Customer name]:[Sales 2012]],0,MATCH(9.99999999999999E+307,tblSales[[#This Row],[Customer name]:[Sales 2012]],1)),"NO SALES")
And yes, since I'm matching off of them for value, I would change the headers to straight "2002" instead of "Sales 2002" but you sort the table on the helper column and then and there you can answer all of your questions.
Hi thanks for this. Just can't figure out how you get the combo box to control the pivot table. Can you please advise?
Cheers
@Kevin.. You are welcome. To insert a combo box, go to Developer ribbon > Insert > form controls > combo box.
For more on various form controls and how to use them, please read this: http://chandoo.org/wp/2011/03/30/form-controls/
Thanks Chandoo. But I know how to insert a combobox, I was more referring to how does in control the year in the pivot table? Or is this obvious? I note that if I select the Selected Year from the PivotTable Field List it says "the field has no itens" whereas this would normally allow you to change the year??
Thanks again
worked it out thanks...
when =data!Q2 changes it changes the value in column N:N and then when you do a refreshall the pivottable vlaues get updated
Still not sure why PivotTable Field List says “the field has no itens"?? I created my own pivot table and could not repeat that.
Hi, I put the sales data in range(F5:P19) and added a column D with the title 'Last sales in year'. After that, in column D for each customer, the simple formula
=2000+MATCH(1000000,E5:P5)
will provide the last year in which that particular customer had any sales, which can than easily be managed by autofilter.
Somewhat longer but perhaps a bit more solid (with the column titles in row 4):
=RIGHT(INDEX($F$4:$P$19,1,MATCH(1000000,F5:P5)),4)
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