Cleaning Up Imported Data – A Recent Case Study

Share

Facebook
Twitter
LinkedIn

Yesterday in Formula Forensics 008 we looked at Elkhans MaxIf problem.

However the solution/formula as presented is the final solution to his problem.

Elkhans original worksheet contained other problems and today we will look at this:

I have attached the orginal file as a sample file you can Download Here.

You will see that the MaxIf cell F13 is returning 0, where it should be showing 0.246

 

Houston, We’ve Had a Problem!

Cell F13 has the same formula we looked at in yesterday’s Formula Forensics: =MAX(IF((Parameter_3=D13)*(Parameter_4=E13),Parameter_5,0))

A quick check of the formula reveals that everything was technically right with the formula, yet the answer is wrong?

To solve this I tried several steps which is the topic of this post:

Examine the logic of the If’s Criteria

The formula =MAX(IF((Parameter_3=D13)*(Parameter_4=E13),Parameter_5,0)) works by calculating the maximum value from the If array.

So step 1 was to look at the logic in the If’s Criteria

That is (Parameter_3=D13)*(Parameter_4=E13)

In cell F15 I entered = (Parameter_3=D13)*(Parameter_4=E13) followed by F9

Excel returns: = {0;0;0;0;0;0;0;0;0;0;0}

This tells me that none of the Cells match the criteria, strange?

Yet manually I can see 4 matching records, below:

Check Cell Length

The next quick step was to look at the length of the text in each cell.

In Column I, I added a =Len(E2) and copied down, there was only 2 characters in each cell, this step eliminated leading or trailing spaces.

Retype the Data

Elkham supplied the source data in an Excel file.

But the Criteria was manually typed by me.

 

So the next step was to retype some of the original data in Cell E2

Wow an Answer, So obviously there was a difference?

 

What is Wrong Here?

So obviously there was a difference between the C1 in cell E2 and the C1 in cell E13?

I checked this in 3 ways

1. Type the value “C1” into Cell E2, without the quotes

This returned an answer 0.08 from F2 as it should have.

2. Copy an old “C1” value to E13

This resulted in the correct answer of 0.246 in F13

 

3. Use a quick Formula

Entering a quick formula

In F17 type =E2=E13

Excel returns False

Showing that the value of cell E2 does not match E13

 

So what is in E2:E12 ?

As I had typed the values into the Criteria Cells D13:E13, I knew what they were, they were a plain and simple “C1”

So what was in E2:E12 ?

Next step was to look at the Ascii values of the 2 characters in Column E.

In K2: =Code(Left(E2,1))

In L2: =Code(Right(E2,1))

Copy both down to Row 13

Bingo !

The Character C in cell E2 wasn’t the same as the Character C in E13 ?

Yet both cells contained a Calibri Font.

If I now type in a spare cells:

F18 =Char(63), Excel displays a “?

F19 =Char(67), Excel displays a “C

Yet Cell E2 is clearly displaying C1 with a First Character Ascii code of 63 which should be a ? mark.

I suspected that it had been copied and pasted from MS Access, So I shot an email back to Elkhan, asking “What the source of the data was?”.

The response came back that “The data had been copied from a Russian (Cyrillic) version of an MS Word File and pasted into an English version of Excel.

I can’t explain what has happened but somehow the character sets and associated values got scrambled when copied the data from the Russian Word Document into Excel

If you have had experiences like this or can explain what has happened please do so in  the comments below:

 

Solution

The Solution was now easy

Use Search/Replace

Copy the contents of cell E1,

goto Search/Replace or Ctrl H

Find: Paste the contents of Cell E1

Replace with: C1

 

Conclusions:

  1. Be careful when receiving data from foreign language files, including word and Excel files
  2. Check summations based on such data to ensure its integrity
  3. Be methodical in tracking down problem cells

 

Lets us know about your Data Transfer Nightmares

Have you had any strange data transfer issues?

Let us know in the comments below.

 

Facebook
Twitter
LinkedIn

Share this tip with your colleagues

Excel and Power BI tips - Chandoo.org Newsletter

Get FREE Excel + Power BI Tips

Simple, fun and useful emails, once per week.

Learn & be awesome.

Welcome to Chandoo.org

Thank you so much for visiting. My aim is to make you awesome in Excel & Power BI. I do this by sharing videos, tips, examples and downloads on this website. There are more than 1,000 pages with all things Excel, Power BI, Dashboards & VBA here. Go ahead and spend few minutes to be AWESOME.

Read my storyFREE Excel tips book

Overall I learned a lot and I thought you did a great job of explaining how to do things. This will definitely elevate my reporting in the future.
Rebekah S
Reporting Analyst
Excel formula list - 100+ examples and howto guide for you

From simple to complex, there is a formula for every occasion. Check out the list now.

Calendars, invoices, trackers and much more. All free, fun and fantastic.

Advanced Pivot Table tricks

Power Query, Data model, DAX, Filters, Slicers, Conditional formats and beautiful charts. It's all here.

Still on fence about Power BI? In this getting started guide, learn what is Power BI, how to get it and how to create your first report from scratch.

13 Responses to “Using pivot tables to find out non performing customers”

  1. David Onder says:

    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 

    • Chandoo says:

      Of course with alternative data structure, we can easily setup a slicer based solution so that everything works like clockwork with even less work.

  2. Martin says:

    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,

  3. JMarc says:

    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

  4. Elias says:

    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

  5. RichW says:

    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.

  6. Kevin says:

    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

  7. Kevin says:

    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

  8. Kevin says:

     
    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.

  9. Bermir says:

    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.

    • Bermir says:

      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)

Leave a Reply