“Is Excel the most dangerous piece of software in the world?”

Stéphane Gaouette, CPA, CA, CA•TI
Managment advisor, DECIMAL

A shocking and thought-provoking question, given that it refers to such a widely-used software program.

The question was asked in February 2013 in the British weekly The New Statesman, in reference to the fact that JPMorgan, the global financial services holding company, lost $9 billion, largely due to its use of Excel. Handling a large number of spreadsheets and files, which had to be completed manually in a non-automated model, had led to disastrous results for the company.

That's all it took to trigger a storm of posts and online debate. Everyone had an opinion – most of them strongly worded – and the headlines didn’t pull any punches:

"Microsoft's Excel Might Be The Most Dangerous Software On The Planet" 
"Wonderful (but dangerous): Excel Spreadsheet Reconciliations"
“Regulators Warn On Spreadsheet Risks (In Quest For Data Excellence)”
« Microsoft Excel considéré dangereux! »


  • The software is used in so many ways that it lacks structure and is hard to maintain;
  • There's a high risk of errors, and even one mistake in an equation can lead to disaster;
  • It can't be automated and must be independently audited;
  • Excessive copy-pasting from one spreadsheet to another increases the risk of mistakes;
  • Many financial managers misuse and overuse the (all-too-often incomplete) spreadsheets they receive;
  • A large number of people depend exclusively on Excel;
  • A lot of time is spent programming, formatting, and reorganizing formulas and functions, and testing the programming;
  • Spreadsheets don't suit the company's specific requirements, procedural changes and complex transactions that have to be programmed;
  • Spreadsheets quickly become unreliable and unsustainable, because they're hard to operate and maintain;
  • Human errors, to the tune of 0.8% to 1.8%, occur during manual data entry;
  • Error-prone, due to such factors as manual data entry, formatting changes, and the chance of accidentally deleting a cell;
  • Collaborating with other users is difficult;
  • No Track Changes option;
  • Assumption and calculation errors;
  • Procedures and systems must be put in place to prevent errors from occurring;
  • Difficulty generating dynamic reports.

As you can see, many of its critics see Excel as the biggest failure of the past century.


The software's defenders argue that it's not the tool itself that's at fault but rather the way it's used. Excel is a tool, just like a hammer – and a hammer can be dangerous if you don't know how to use it properly.

These people argue that it's easy to use: everyone knows it, it's inexpensive, it's installed on every employee's workstation, it requires no dedicated personnel, and it's possible to implement a certain number of controls. It also supports data processing with countless (albeit unvalidated and untested) parameters.

In short, everyone has their own more or less well-thought-out opinion. However, one thing is clear: there is a growing awareness of the risks associated with corporate use of the software, and these risks are increasingly proven by telling examples.


As many people have said, the problem isn't the tool itself. It's not even the users. The problem is how and for how long the tool is used. Using it for short-term projects isn't a problem. I'm sure most of you have used Excel to complete various small, on-demand tasks: to quickly analyze data or present a simple report.

The danger ratchets up a notch or two when the organization decides to develop and maintain an organization-wide, Excel-based system. Anyone can dream up a data interface, but it takes a software developer to know what's hiding behind the data entry screen.

Unfortunately, the lack of IT services within most organizations has forced staff in every department – including accountants, data entry clerks, managers, and other resources – to develop their own programs. However, Excel wasn’t designed to be a programming development tool, especially when the development is being done by non-specialists.

Here’s a short list of the features Excel does not support: quality assurance, process management, configuration management, track changes and supporting documents. Any internal audit department will tell you: No matter what you do, Excel is not a secure system.

Excel is a very good tool. So good, that some people use it to perform tasks for which it was not designed.


When it comes to budgeting, costing, dashboards and management reports, using the first tool that comes to hand just isn't good enough. DECIMAL's fully integrated, limitless and risk-free solution can help your organization avoid the problems associated with using Excel.

The Decimal Suite is an integrated, structured solution with proven functionality that can track changes made by multiple users, enabling them to access different analysis views, run different scenarios and consolidate data from a variety of sources. The centralized data set enables multiple users to work on the same document, simultaneously and securely.

Centralizing data saves a great deal of time and frees up users to focus on analyzing rather than on entering information. Flexible and fully customizable, the Decimal Suite is the perfect management tool for achieving organizational objectives and helping managers make informed decisions.


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