Spreadsheet Design

XL Dev Con – The Fast Standard – Morten Siersted

Morten Siersted, from conference sponsors http://www.f1f9.com, talking about FAST, a simplified set of rules his company is using to build clean models.

Its interesting to see this take on an approach to a standard, F1F9 have tried to give it an independent life, by passing it on to 3rd parties, I guess the concept is like open source, but for a spefification… if that make sense – it does to me, you can read all about it here

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F1F9, Help, Calculate, or Help Breakpoint, my monies of the former!

As i have said before I liked what Morten had to say, I not sure everyone else did. I don’t think you would use the FAST standard for every model you every builid, but I’m certain that its principals would make a good many models a lot simpler to user and easier to maintain, I can think of a few around here that would greatly benefit!!!

XL Dev Con – The Excel Window – Simon Murphy

Simon, the driving force and brains behind the whole event and started us off with a presenation on architecture. It was a great start to the day,

Simon asks N-Tier Applications with Excel, what's the impact?

After describing how Excel solutions grow, into an N Tier solution, or why they get built that way in the first place Simon looked at the implications to maintenance  and robustness.

Why did he call his talk the Excel Window? Well Simon’s view is that the Excel Windows is “his”* view of the corporate world, and thus, what happens in that window, to some extent drives the org. – well somthing like that, Excel is the window, and there all this data and informaiton so where behind it…

*or the app users, I guess

UK Excel Developer Conference 2012

Its that time again…

The last UK XL dev con back in 2010, was a great event, some say the best London centric Excel developer event of the year.

Good news. Simon is doing another one next year (2012), Wednesday 25 Jan, The Skills Matter Exchange, London.

You can book a ticket here, great value at 200 quid:

http://www.codematic.net/donations.htm

Here’s the outline agenda:

  • Excel Business Intelligence
  • PowerPivot and DAX
  • Migrating from VBA to ExcelDNA with VB.net
  • Effective Excel Add-ins with VSTO
  • Technology independent software development
  • Beer and chips (and gravy) AKA Lunch
  • Practical advice on commercialising your add-ins/workbooks.
  • Various approaches to XLL development
  • Excel and XML
  • Quick tips for effective VBA use.
  • Programming paradigms and how they can help or hinder, a history lesson
  • A smart way to build spreadsheets
  • Beer & Curry AKA after event social!

More details of who’s doing what here – impressive, I’m sure you’ll agree!

Notice there’s a mix of how to technical stuff and more cerebral approach based stuff. I know that a number of Excel big hitters are lined up to present, and the level of folks who attend is always nice and high; its a great event to be at.

You can really get behind some of the issues and questions that have been bugging you, with people who are on the same page as you, and have eirther been there themselves or have some decent ideas about what to do!

Aside from the content of the talks and so on, its a good chance to meet many of the Excel tribe in person, there nothing like actually seeing a persons face, even if its mine!

Book your place now:  http://www.codematic.net/donations.htm

So, I hope to see a lot of you there and look forward to meeting you if your coming, I might even go for the curry and beer this year.

If you can’t come heres a slightly funny excel based picture:

“na-na-na-na-na-na-na-na BATMAN!”

The MIE Podcasts – Charles Williams

Charles Williams is probably best known for his work in Excel calculation speed and VBA performance, not to mention the worlds most famous Excel Addin Name Manager. In truth, he’s a expert in many areas of Excel and on top of all this he’s a great bloke. In this podcast we got down and dirty with Excel performance, uncovering some interesting insights along the way. It was a true pleasure talking with Charles.

Charles the First - King of Speed!

Charles in the founder of Decisions Models, a consulting firm specialising in Excel development, and the farther of the FastExcel addin, we talked about this addin and how it works and also his addin loader tool. This is one for the archives!

Thanks to Charles for making the time and sharing his knowledge with us all.

A rant on Excel and Bad Ideas.

The great thing about the internet is that anyone can share their thoughts, the problem with the internet is that anyone can share there thoughts. A classic dichotomy if you will.

We see this all the time, people talking utter, utter rubbish about things they don’t understand. As “organisations” have started to blog more and more this issue has increased. The way I see it is like this… If you run “Mega Corps” would you want me bloging for you? I probably wouldn’t. You see I’m not a talented writer, my spelling and grammar are poor and I’m not adept at making my point – as I will now prove. So “Mega Crops” ask the people who can do these things well to blog for them. What actually makes for a good bloger is someone who can think well! See, a bad idea expressed well is still a bad idea. What makes a great bloger is someone who can think and write well – and these types are rare. But still, what would you rather have, an ill-conceived observation expressed elegantly or a quality observation just expressed?

Which leads me to these two blog post, the first one suggests that people who use Excel in the supply chain are doomed, and the second one adds more fuel to that fire.

Beware Supply Chain Excel Users—YOU are DOOMED!!!!

Excel doesn’t excel in all cases…

Now I need to be careful here, I don’t what to offend anyone.

Equally I’d like to address the lack of understanding and insight, or at least offer a counter view. I have some grounds to make these observations, being somewhat familiar with Excel and having worked in supply chain for the last decade or so.

Basically both articles point out the limitations of Excel, principally by comparing the differences between Excel and a Generic ERP system. For example:

“Excel has features that can calculate safety stock by using prebuilt basic formulas such as moving average, standard deviations forecasts etc. Keep in mind that by doing this, an organization will not have the ability to see the entire supply and demand relationship. On the other hand, when the same safety stock is calculated within an application, it will provide visibility to outstanding supplies that need to be replenished; orders can be planned for production; and it can calculate how quickly organizations can turn a forecast into a deliverable product.”

Khudsiya Quadri, Technology Evaluation Centers

And

“I completely agree with the author that there is a big risk to SCM Professionals who rely too heavily on Excel.  There are all the reasons listed in the article such as  lack of collaboration, visibility, control and no ability to perform “what-if” scenarios.  I would like to add some additional thoughts to this discussion.”

Monique Rupert,  21st Century Supply Chains

So, Excel has limitations creating what if scenarios, and pre built basic functions!! Clearly not Excel experts! Another common theme is that Excel is not very good for collaboration, information sharing and data security…

It is almost impossible to control the integrity of spreadsheet data and access to the spreadsheet.  With multiple people accessing the spreadsheet and no security, how can anyone have any confidence in the data?

Monique Rupert,  21st Century Supply Chains

Well true. Sharepoint (etc.) might help here, but that’s another issue. So basically don’t use Excel as a database. Fair enough but…

Comparing Excel to an ERP system is like comparing a Motor Bike to a Train Network. It’s just stupid. Telling people not to use Excel because it does not have the same capabilities as an ERP system is likewise really bad advice. Excel is different to an ERP system, we could easily re frame the argument the other way around and draw the conclusion that ERP system are the work of the Devil!

In fact, lets do just that.

Beware Supply Chain ERP Users—YOU are DOOMED!!!!

ERP systems are slow expensive complex beasts, with poorly documented calculation methods, inflexible font ends, and limited reporting capabilities. I recently talked to a number of supply chain professional and was shocked by how many of them are using their ERP systems in blind faith that the system are optimised for their needs. In the fast passed global supply chains of today, how can these default settings and calculation models possibly be right for your business?

Consider yourself doomed if you ever find yourself using an ERP system for any of these:

Reporting and Analysis: ERP system can out put reports in a number of formats, but typically they cant build well constructed dashboards, which are tailored to your companies specific needs, and/or ones that can be quickly adapted and changed over time as the needs of the business change. And forget it if you want to do some sort of analysis that the System Architect didn’t think you’d need to do in the 2 month he was specifying the system for your company 3 years ago. (Not that that would ever happen of course…).

Changing the model: ERP systems provide various forecasting tools, is getting the best results from them a skill or a science? Do you even know what equations are being used, it’s unlikely because this is the IP of the vendor, and what about data sources, is that data from the Spanish plant accurate, if it’s not can you do anything about it? Not all that flexible are we!

Your team just grew: Better get your wallet out…

You want someone form out side the organising to use the system: No.

You have a new data source that you’d like to add to the model: Humm, can you see where we’re going…

And so on…

In conclusion neither ERP systems or Excel can doom your supply chain and comparing one against the other as a way to high light a weakness is a logical flaw. Neither ERP systems or Excel are inherently good or bad, badly designed and/or used spreadsheets are a business risk, just like a poor quality ERP system or ones that are used poorly are a risk. Each “system” has strengths and areas where their use makes sense, and this are extremely well document. Likewise the “miss use” of Excel and the motivations for this are also well document, and note – not all of them are unreasonable.

I take exception to the two blog posts because as well as misrepresent the capabilities of Excel, they also give poor or misleading reasons as to why it’s use is dangerous, also they both take one or two valid, but already extremely well understood points, and extrapolate them to reach irrational end points.

So were doe this leave us?

Well, here are some of my thoughts on what you should do to help you avoid risks if your using spread sheets (for anything really)

  • Design you spread sheets well from the ground up (here, and here for help)
  • Understand connected or discounted data sources
  • Learn how to connect to enterprise data bases.
  • Learn about versions, and version control and try to apply it
  • Think about risk, and except it explicitly if you have to

And there ended the rant ;-).