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

Microsoft's calculator is partially to blame for JPMorgan losing $9bn, and a lot more besides.

Is Excel the most dangerous piece of software in the world? Baseline Scenario's James Kwak reports on a little-mentioned aspect of the notorious "London Whale" debacle at JPMorgan, where Bruno Iksil headed a proprietary trading team which made losses of up to $9bn.

It turns out, Kwak writes, that Excel was partly to blame:

To summarize: JPMorgan’s Chief Investment Office needed a new value-at-risk (VaR) model for the synthetic credit portfolio (the one that blew up)… The new model “operated through a series of Excel spreadsheets, which had to be completed manually, by a process of copying and pasting data from one spreadsheet to another”… After the London Whale trade blew up, the Model Review Group discovered that the model had not been automated and found several other errors. Most spectacularly,

“After subtracting the old rate from the new rate, the spreadsheet divided by their sum instead of their average, as the modeler had intended. This error likely had the effect of muting volatility by a factor of two and of lowering the VaR…”

Kwak wonders if the very ease of use that Excel offers — allowing people with no programming experience to knock together what are, in effect, relatively advanced applets — also makes it dangerous to use in most sensitive situations. There's no debug, no audit trail, and no way to test why a spreadsheet returns the value it does. Similarly, training for Excel, where it exists, tends to ignore the importance of elegant and well-designed code, leading to legacy spreadsheets being used with internal workings which are opaque to all but their original creator, who may have left the company 20 years earlier.

The problem is, though, that Excel is the worst way to run a company's software other than all the other ways. The fact that it's capable of being programmed by the people who will end up using it means that it might enable hacked-together code, but it also prevents exactly the sort of corporate bloat which leads to people circumventing their company's software in the first place.

Bill Gates threatens the world with Microsoft Office in 2003. Photograph: Getty Images

Alex Hern is a technology reporter for the Guardian. He was formerly staff writer at the New Statesman. You should follow Alex on Twitter.

Grant Shapps on the campaign trail. Photo: Getty
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Grant Shapps resigns over Tory youth wing bullying scandal

The minister, formerly party chairman, has resigned over allegations of bullying and blackmail made against a Tory activist. 

Grant Shapps, who was a key figure in the Tory general election campaign, has resigned following allegations about a bullying scandal among Conservative activists.

Shapps was formerly party chairman, but was demoted to international development minister after May. His formal statement is expected shortly.

The resignation follows lurid claims about bullying and blackmail among Tory activists. One, Mark Clarke, has been accused of putting pressure on a fellow activist who complained about his behaviour to withdraw the allegation. The complainant, Elliot Johnson, later killed himself.

The junior Treasury minister Robert Halfon also revealed that he had an affair with a young activist after being warned that Clarke planned to blackmail him over the relationship. Former Tory chair Sayeedi Warsi says that she was targeted by Clarke on Twitter, where he tried to portray her as an anti-semite. 

Shapps appointed Mark Clarke to run RoadTrip 2015, where young Tory activists toured key marginals on a bus before the general election. 

Today, the Guardian published an emotional interview with the parents of 21-year-old Elliot Johnson, the activist who killed himself, in which they called for Shapps to consider his position. Ray Johnson also spoke to BBC's Newsnight:


The Johnson family claimed that Shapps and co-chair Andrew Feldman had failed to act on complaints made against Clarke. Feldman says he did not hear of the bullying claims until August. 

Asked about the case at a conference in Malta, David Cameron pointedly refused to offer Shapps his full backing, saying a statement would be released. “I think it is important that on the tragic case that took place that the coroner’s inquiry is allowed to proceed properly," he added. “I feel deeply for his parents, It is an appalling loss to suffer and that is why it is so important there is a proper coroner’s inquiry. In terms of what the Conservative party should do, there should be and there is a proper inquiry that asks all the questions as people come forward. That will take place. It is a tragic loss of a talented young life and it is not something any parent should go through and I feel for them deeply.” 

Mark Clarke denies any wrongdoing.

Helen Lewis is deputy editor of the New Statesman. She has presented BBC Radio 4’s Week in Westminster and is a regular panellist on BBC1’s Sunday Politics.