The COVID-19 pandemic has offered moments that will live long in data folklore...

The COVID-19 pandemic has offered moments that will live long in data folklore. I have written before about the ‘mutant algorithm’ and its impact on a generation of students. There’s also the use of clumsy Powerpoint slides hastily arranged to deliver a complex message, which in the age of memes ended up becoming one.

Figure 1: One of 2020’s favourite gifts. Professor Chirs Witty’s mug

Perhaps the most painful incident for those of us who work with data was when around 16,000 positive cases were left out of the official daily figures because of an error in Excel. I followed the outrage online and shared the feeling of incredulity that such essential data analysis in time of crisis was being done using Excel. But at the same time, I wasn’t surprised. It is a well-known fact that Excel is the world’s most popular programming language. It allows domain experts to work with data independently from IT. This is an opportunity and a risk as Public Health England painfully learned.

Excel always divides opinion amongst data leaders. In housing, as in all other industries, the use of spreadsheets is widespread and gives analytics teams absolute nightmares. There are countless examples of Excel spreadsheets acting as the key data source for essential business processes. There are instances where spreadsheets are so complex that experienced developers are afraid to ‘touch’ them. But amongst all the hate, there’s a recognition that Excel helps users get closer to their data, that data is becoming fundamental for all jobs and that Excel is one of the gateways into data literacy. Excel is here to stay and finding a place for the humble spreadsheet amongst the myriad of analytics tools is one of the key decisions data leaders need to make.

One of these new analytical tools growing fast in the sector is Power BI. This tool was released by Microsoft to the general public in 2015 and has continued to gain momentum with every new release. Power BI evolved from within the Excel product, initially as a set of add-ins which gave users extra functionality and later as a standalone tool for advanced analytics. Users find the transition from Excel to Power BI much easier than with other tools. Once familiar with Power BI users can start working with visualisations to represent their business data and share their analysis across the organisation. The ability to represent quantitative information in accessible visualisations is a powerful skill which has the potential to surface new insights which were hidden in plain sight such as the famous case of John Snow’s map of cholera infection clusters in Soho in 1854.

Figure 2: Another pandemic, another data visualisation. John Snow’s pioneering map

Visualisations that help us understand complex data have been prevalent during the Covid-19 pandemic with notable examples from The Financial TimesThe New York Times and Our World in Data. Scientific evidence backed by extensive data and presented in clear and engaging visualisations have helped governments make very difficult decisions and explain them to the public. These actions have literally saved lives and are extreme examples of how data informs decisions which ultimately drives action. This is what most organisations in the housing sector are grappling with. How to become more data data-driven, how to use the large amounts of data in their systems to inform the right decisions for the benefits of residents and colleagues. This Coronavirus crisis has only accelerated the urgency of this change.

At HouseMark, we have recognised the need for improving skills in data analytics across the sector. We have been running our data training programme for the last three years including courses on Power BIHousing Analytics and Excel. Over this period, we have trained more than 200 housing professionals in the skills they need for bringing data to life and using it to make decisions. We have developed housing-specific datasets for the courses as we know that learning new tools using repairs or rents data helps participants apply the concepts directly to real-world examples. We have also built an online community with everyone who has taken part in the courses to share their knowledge and experiences working with data in housing.

So next time you are in front of execs in your organisation ready to present the findings from your analysis which started as a concept in Excel and evolved into a sophisticated Power BI dashboard; remember the words of Professor Chris Witty on a cold Halloween night in 2020 and make sure you bring a clicker!

Our full 2021 data training prospectus is available hereVisit our webpage for more information or contact

PS Here are a few great visualisations I have selected. If you have any others you would like to share, please let us know at and we can add them to this article!

Figure 3: The topologist’s map of the world.

Figure 4: Twitter emoji map:

Figure 5: Show your stripes by Ed Hawkins