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Reader Bert van Zandbergen sent me a cool modification to the instruction file in How to: highlighting cells using the rollover technique in Excel to include years and months - not just rows and columns. He writes:

I am an enthousiast reader of the blog 'Option Explicit'. I changed the formula (see below) and made a version for showing Years and Months. Now you can use this tool for Management Information. This fantastic tool, combined with Named Dynamic Ranges gives the ultimate solution for making awesome interactive dynamic Excel charts. As soon as possible I will show you an example.           

Bert van Zandbergen, Beekbergen  - The Netherlands 

You can download the file, here: Rollover_MI model version 1.xlsm

Thanks Bert!

Author: Unknown Labels: Advanced Excel, Project Management, Rollovers

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In the last post, A Dynamic Dashboard for Project Durations and Costs in Excel, we talked about using VLOOKUP as means to map references to their costs.  At the end of the post, I admitted that I didn't really like the solution.  Specifically, I didn't like how the user had to type in each reference manually and then go back and ensure their numbers were correct (for example, if execution is nine months long, the user would need to ensure they type the number 2, nine times).  In this post, we'll talk about how to automate this process.  When we're finished, you'll only need to type the number 9 into a box and the rest will update automatically.  

The Advanced Method

Step 1: Use the REPT formula

The REPT() formula (short for "Repeat") allows you to repeat a character a certain amount of times.  For example, if A1 has the formula =REPT("A", 6), then A1 will display the value "AAAAAA."  Now think about how that might be useful here.  We could simply input the number "6" for IT Services in the Execution phase and Excel will generate a reference string "222222."

Consider below:

In this case, =REPT(C$11$, C3) is telling Excel to repeat the value 1 (our reference to planning) a total of two times.  In other words,  =REPT(C$11$, C3) -> =REPT("1", 2) -> 11. (Remember, "11" is two 1's, not eleven.)

Step 2: Create the reference string

Now concatenate each string reference (using the concatenation operator "&") to form the entire reference string.

  

Step 3: Read from the reference string using the MID formula into your References Table

The MID formula allows you to take a string and read its characters starting from a specific position to a certain character length.  For example, =MID("Jordan",2,2) returns "or" since the first 2 tells Excel pull from the second character in "Jordan" and the second two tells Excel the amount of characters to return.  For our purposes, we'll only need to return one month at a time.  And since our reference table incidentally uses numbers for months, we'll reuse those numbers to tell the MID formula our desired character position.  When you supply a character position greater than the character length of the given text string, MID simply returns nothing.  

Above, we tell Excel to take the corresponding reference string for IT Services and use Month 1 to pull from position one in the reference string. Fill in the information going across, then down.  

Consider what we've done so far.  Now when you change the information in your Months in Step table, the reference strings change, which makes updates to the Reference Table automatically!

  

Step 4: Convert references to numbers in your Values Table

We have a small problem. Our Reference Table may be displaying the correct information, but it's actually displaying the information as text and not a number (this is because we used String formulas above, which work on and return text).  If we try to add the the numbers for the IT Services row in our Reference Table above, the result will actually be zero since, despite appearances, no numbers actually exist in the row.  Luckily, the fix is simple.  We'll use the VALUE() formula to convert the strings back to numbers.       

Step 5: Ditch VLOOKUP.  We don't need it.

VLOOKUP is best used to look up strings, not numeric values.  I've updated the look up table below.  Take note that each phase is actually intrinsically encoded: Planning is already in row 1; Execution in row 2; and Maturity in row 3.

In this case, we need only use the INDEX() formula.  The INDEX formula allows us to pull from a specific row and/or column in specified range.  For example, we could take the last column above and use the numbers in our Reference Table to identify the desired row.  Take a look below:

The Values Table uses 1 in the References Table to pull from the first row of our lookup. 

Step 6: Use IFERROR for months with zero values

Another small problem.  The INDEX formula above is reading in blank values and returning errors!  You'll need to tell Excel to return $0 for those months.  To do so, you'll use the IFERROR formula.  IFERROR works by attempting to execute a given formula; if the formula returns an error, IFERROR will direct Excel to return another value instead of an error.

Take a look: 

Step 7: Sum the Values Table, then graph

Summary
Hopefully that wasn't too bad.  I wanted to show how many different formulas can interact to create an automated dashboard.  Of course, you could tighten some formulas up.  For example, instead of using VALUES, you could simply use the "--".  And, you could even do away with the IFERROR by retooling your lookup table.  I'll leave that up to you.  


Something to try...
Use the reference table and conditional formatting to create a gannt chart!




We're still missing some desired functionality.  Wouldn't it be neat to be able to set the date when each project begins?  We'll talking about that in Part 3.  Don't miss the riveting, final conclusion!


Download the example file: Dynamic Duration Example.xlsx

Author: Unknown Labels: Dashboards, Dynamic Charts, No VBA, Project Management

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Make sure to checkout A Dynamic Dashboard for Project Durations and Costs in Excel (part 2) for the example file!

Let’s say you are the manager of a portfolio of projects at your company.  While each project under your aegis is different, they have a few things in common; specifically – and for the sake of our example – they all go through (or, are currently in) three different phases, and each phase has a different cost per month, but the cost doesn’t differ between each project.  In our example, the phases are:

Phase Name Cost of each stage per month
1. Planning $250/month
2. Execution $500/month
3. Maturity $125/month

The idea is to capture both the cost in any given month and the overall cost over the life of the project.  For example, you have an IT Upgrades project in your portfolio.  You think that you will spend two months in Planning, nine months in Execution, and one month in Maturity after which the project will be closed.  Thus, the overall cost of your project is expected to be,

Planning @ two months: 2 months * $250 $/month  = $500
Execution @ nine months: 9 months * $500 $/month = $4500
Maturity @ one month: 1 month * $125 $/month = $125
Planning + Execution + Maturity =  $500 + $4500 + $125 = $5125

The problem is that each project is different.  One project might spend more time in the first phase than the other.  Moreover, for some projects you have a good idea of how long they will stay in each phase, and for some you are a bit less sure.  Boy, you say, wouldn't it be nice to change how long a project stays in each phase to compare costs.  Wouldn't it be nice to see it on a chart?  Let's see what we can do.

Using a VLOOKUP might seem like an obvious choice for our solution.  Here's how to do it.   

The Dynamic VLOOKUP Method

Step 1: Create the VLOOKUP table
Since you know there are three projects, you could encode ids into a lookup table numbers as follows.

Step 2: Create a Reference Table
The Reference Table is a time-series table that holds the numerical references to your VLOOKUP table.  If IT Services has two months of Planning, then the Reference Table will show two 1's in the first two months, respectively.

Step 3: Create a Values Table to map each reference to its monthly cost using VLOOKUP
Now, you'll make another table that is essentially a mirror image of your Reference Table. This table, however, maps each reference to the correct cost.  So, for Month 1 in the Values Table, VLOOKUP will use the corresponding reference (1) in the Reference Table to indicate the project is in the Planning phase and the associated cost is $250.

Step 4: Sum the Values Table, then graph

Summary
Our dynamic VLOOKUP() method works: the manager (that's us) can replace the values in the Reference Table to update how long a project stays in each phase.  We would simply repeat numbers in the Reference Table in the amount of months a project is in a particular phase.  Our Values Table automatically updates based on each change.



So here's the thing.  I don't like this method at all.  For one, we need a VLOOKUP in for every month, for every program.  Our example only displayed a few projects in a small time frame, but the real world might have many projects over many years!  That's a real problem because VLOOKUPs can become computationally expensive as our spreadsheet grows.

And there's another problem, too.  The manager – that's us, remember – must hand-jam the references in for every month. What if there are many years to account for?  We could Copy/Paste to make life easier, but this method is so very, very error-prone.  There should be a way for us to simply enter the months a project is in a given phase and have Excel automatically generate all the required reference information.

Let's talk about how to do that in the next post.

If you're having trouble with the work above, take some time to see if you can recreate your own version in Excel.  Even if you have followed everything so far, consider the VLOOKUP method and the importance of using numeric references.  They will play a very key role in part 2. 


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Now Available: A Dynamic Dashboard for Project Durations and Costs in Excel (part 2)

Author: Unknown Labels: Dashboards, Dynamic Charts, No VBA, Project Management