Spreadsheets: The dark matter of ITFelienne Hermans (@felienne)

95% of all U.S. firms use spreadsheets for financial reporting

50% of spreadsheets form the basis for decisions

Spreadsheet exist ‘under the radar’

Spreadsheets can have a long life, 5 years on average

Average sheet is used by 12 different people

Only 33% of spreadsheets has a manual

Complex spreadsheets lead to disaster

The European Spreadsheet Risk Interest Group (Eusprig.org) collects horror stories

Loss 2.4 million dollarsCause typo

Loss 2.4 million dollarsCause typo

Loss 24 million dollars

Cause copy-paste error

What can we do?

No docs, errors, long lifeIt looks like…

No docs, errors, long lifeIt looks like software!

In software, tools have been created tohelp programmers understand code

We bring understandability tools to spreadsheets

Then we tried the tool in practice

Users started diagnosing with the diagrams

“This is too complex”

“This arrow is too fat”

Move C11:F20 to POA Project

We tried the tool in practice again

Complicated formulas still got in the way of understanding details

This formula can be simplified

The analyses are combined in ourtool PerfectXL

The analyses are combined in ourtool PerfectXL (www.infotron.nl/strata)

We build tools to visualize and improvespreadsheets

What can we learn from the success of spreadsheets?

Most alternatives still look like this

BI Spreadsheets Complex Simple

BI Spreadsheets Complex Simple

Plan Serendipity

Spreadsheets: The dark matter of ITFelienne Hermans (@felienne)