Excel is now 40 years old and it’s capable of some amazing things. Let’s not forget some of the mistakes made by users and serious bugs by Microsoft along the way.
First a reminder of some Excel bugs and how Microsoft never seems to learn from their mistakes.
Excel bug adding rows and columns
Back in 1998 Microsoft had a serious embarrassment with a series of Excel calculation bugs and failed patches. Office Watch covered the unfolding drama in detail, much to Microsoft’s annoyance.
It started with the revelation of a simple Excel 97 bug where an inserted row would not be included in the SUM() correctly. Microsoft eventually/reluctantly admitted the bug and released a patch.
But that wasn’t enough. The patch fixed only part of the bug (adding rows) but not the related bug (adding a column). So yet another patch was required. There was another faulty patch in the midst of all that.
In those days, downloadable patches weren’t easy to find and most users continued unaware of the dangers.
Some things never change
Looking back on our coverage of Excel bugs over 25+ years, Microsoft attitude to bugs hasn’t changed much. Even in 1998 with Excel 97, it was “déjà vu all over again”.
Denial – initially there’s a refusal to believe the bug exists at all. The simpler the bug is, the harder it can be to get Microsoft staff to accept the bug is real.
Hiding – once Microsoft realises there is a problem, they’ll deny the bug publicly for as long as possible. Sometimes Knowledge Base articles aren’t publicly released until there’s a patch available, leaving customers in the dark in the meantime.
Deflecting – when forced to go public and acknowledge the problem, it’s done in as low-key way as possible with language that deflects the scope. Back in 1998 customers were assured the bug only happened in “complex circumstances” when in fact all it took was adding a new row or column!
Faulty Patches – Microsoft Office has a long history of faulty patches. Patches that won’t install, don’t fix the (whole) problem or cause more bugs!
Forget – Microsoft’s corporate culture has a very selective memory. Mistakes are quickly forgotten which might explain why the same problems keep happening year after year.
Excel Row insertion bug
In Excel 2010 and 2013 there was another bug involving the addition of rows or columns to the end of an existing table. Similar to the problem back in 1998!
Excel bug: Row Insertion and cell ranges
65,535 and 65,536 Excel bug
This was astonishing.
Excel 2007 had a bug where cell results around 65,535 to 65,536 would show as 100,000!
Excel’s problem with 65,535 & 65,536
Excel addition strangeness
In 2008 Office Watch reported on more Excel addition worries.
Some of it was the inevitable floating point number issue that affects all computers.
It means that Excel can’t handle simple addition as well as a handheld calculator or an elementary schoolchild.
But it goes beyond that because sometimes the order of the numbers or grouping can affect the result.
Excel Blooper Reel
The Guardian has an Excel Blooper Reel of serious mistakes by users that have had huge, sometimes world-changing results.
Excel changed economic policy for the worst
Back in 2010 an academic paper concluded that government spending should be limited during a fiscal crisis. This was seized upon by some as ‘proof’ of their existing bias against government spending.
However the calculations in the paper where wrong. As more country data was added to the spreadsheet, the Average() and other results weren’t updated.
The conclusion that high spending led to a 0.1% decrease in economic growth across various countries was wrong. The real figure was 2.2% Increase.
But that news came too late and some economic troubles were made worse at that difficult time.
Office Watch explains the bug in detail at Excel’s effect on economic policy
Nobel Laurate Paul Krugman explains how the Excel mistake affected the global economy as “austerity has been sold on false pretences”.
Gene Naming
A widespread mistake not mentioned by The Guardian is the trouble geneticists caused themselves by importing .csv test files incorrectly. The gene code MARCH1 was converted into a date, 1234E5 is turned into a number etc.
Instead of importing text via the Text Import Wizard or Get & Transform, they would just open the .csv directly leaving Excel to guess what to do.
Conversion mistakes appeared (might still appear) in thousands of sheets.
Eventually both sides worked to fix the problem. Geneticists changed some code names so Excel would not be confused.
Microsoft added Automatic Data Conversion to Excel 365 and Excel 2024 to address the broader problem of text importing.
Unintended collateral intrusion
“Unintended collateral intrusion” was the description of an Excel formatting mistake which changed 134 phone numbers which were then ‘wiretapped’ wrongly by a UK spy agency. See page 39 of this report.
J P Morgan
JP Morgan once suffered a $6billion trading loss due to faulty Excel spreadsheets calculating financial risk.
Debug to understand and fix Excel formulas
