Unlocking Kenya’s 2009 Census Data

Kenya conducted its last population and housing census in 2009. Total population was initially estimated at 38.6 million, but this has now been revised to 37.7 million. Since population is a key factor in planning, let us review the census data with the aim of enhancing its dissemination and utilization.

Data Review

For this project I used a summary of the 2009 Kenya Population and Housing Census as the main data source. The data was downloaded from the Kenya National Bureau of Statistics (KNBS) website. I first transposed the data from a Pdf document to an Excel spreadsheet, only to discover that I could have downloaded the data from one of the data sharing platforms as a text file.

Some time was spent assessing the quality of the data in various dimensions. Here are some of my key findings:

  1. Accessibility – The 2009 census data can be accessed and downloaded from the KNBS Visualization portal. Census data are aggregated to current county and former district level and includes male, female, and total population, no. of households and census area in sq2.
  2. Accuracy – KNBS casted doubt over the accuracy of the 2009 census when it reduced the population for Garissa, Mandera, and Wajir by 40% citing inconsistencies with previous censuses. This resulted in an outcry from political leaders, since population is a key factor in the allocation of revenue to the counties.
  3. Currency – The Kenya housing and population census is conducted every 10 years, so the original and revised 2009 census estimates are very much in use. This is worrying, since Kenya’s current population is estimated to be around 49 million, roughly a 30% increase from 2009. Occasionally KNBS releases population projections, but it appears these rely on historic net growth rates at the level of the former provinces.
  4. Relevance – Many planning activities will benefit from access to census data disaggregated by age group or income level, but data dissemination is primarily geared towards the aggregated numbers. As a result, most use cases for census data rely on aggregated data from disparate and non-authoritative sources. KNBS ought to address this pitfall by disseminating its statistics in a more integrated and meaningful way.

Data Visualization

An entire section of the KNBS website is dedicated to the 2009. Rather annoyingly the data is in Pdf format and can’t be previewed on the website. Download of a few samples suggest that all data is presented in a table format.

Interestingly the KNBS home page provides access to not 1, but 6 data sharing platforms. Some of these platforms disseminate data in the form of tables and reports, others appear in disrepair and one of them bombards you with column charts in all colors of the rainbow.

If you are lucky you’ll find a map, but it’s unlikely to give you all the information that you are looking for. Based on this I decided to build a Web App that would unlock the summary results of the 2009 census.

The Web App was built with the ArcGIS Online Basic Viewer web template. This is a basic template that accentuates the web map and contains a limited number of tools in a floating pane. The Web App was developed based on the following considerations:

  1. Purpose
  • Provide public access to key facts from Kenya’s 2009 population and housing census at the county level in a novel and engaging manner.
  • Use of the app will not require advanced technical skills or knowledge of GIS.
  1. Design – The app will embrace the following design considerations:
  • Be clean and simple and maximize real estate for the map itself.
  • Contain a small number of layers with moderate use of color.
  • Provide summary census facts through a pop-up window.
  • Offer a limited number of utility tools within a single pane.
  • Use responsive design to offer a good user experience across all devices.
  1. Functionality – The Web App offers the following navigation, search, and query capabilities:
  • Navigate the map with pan and zoom using mouse or screen controls or the home and zoom buttons in the floating pane.
  • Access census data for a county of choice through a pop-up window by clicking the country on the map.
  • Find a county on the map and access its census data by typing a county name into the search box in the floating pane window.
  • Get to know the name and designation of a protected area (e.g. Mt. Elgon National Park) by clicking it on the map.
  • Turn layers on and off, view their legend and change their transparency by clicking the layers button in the floating pane.
  • Change the basemap and share or print the map by clicking the respective button in the floating pane.

The Web App has been embedded below, so take your time to interact with it and learn the census 2009 results for a few of Kenya’s counties.

Developers Corner

The 2009 census data was downloaded from the KNBS website and the county boundaries were downloaded as a layer package from ArcGIS Online. Both datasets were imported into an ArcGIS Pro project database. Within ArcGIS Pro the two datasets were joined, and the result was published to ArcGIS Online as a hosted feature layer.

Using the ArcGIS Online Map Viewer, a new Web Map was created that includes the hosted feature layer with the census data and a public ArcGIS Online web service that contains Kenya’s wetlands and protected areas. The pop-up window for the census data was configured in the Map Viewer, and included the following steps:

  • Changed the pop-up title to read “Census data for [County Name]
  • Configured the attributes displayed in the pop-up window by toggling their visibility and changing their alias.
  • Added attribute expressions to calculate population density, household density and average household size.
  • Added a pie chart showing the number of males and females.

From the Web Map a Web App was created with the Basic Viewer web template. Configuring the Web App was straightforward and could be validated through the preview. The search settings were restricted to county name and configured to use auto suggestions. This makes it easy to find a county even if one doesn’t remember its exact name.

Use Cases

The Web App that has been developed supports only a few basic use cases; anyone with an Internet connection can now view summarized census facts for each county at the click of a button. This demonstrates how web apps can enhance access to census data and complement the statistical information that is contained in reports and tables.

It’s evident that most use cases for census data and national statistics require more detailed information. For instance, a supermarket chain that wants to open a branch outside of Nairobi, needs demographics at sub-county or preferably ward level for each of the 47 counties. In addition, they need information on income levels to determine consumers’ disposable incomes.

Here is another example. To ensure that there are enough schools and qualified teachers across the country, governments needs access to demographics. Census data from 2009 is hardly useful and annual projections on population are direly needed. In addition, national statistics on labor and jobs are needed to create educational policies, institutions, and programs. The existence of an integrated national statistical information system would facilitate this process.

Kenya has no lack of statistical data, but lacks a national statistical information system that disseminates the needed information and informs decision-making. The devolved system has made matters worse, since national datasets are now cut into 47 county datasets. The solution to this is an integrated data repository with clip, zip, and ship capabilities.

The Unites States Census Bureau does a great job in providing information about the American people and economy. Not in the least because they have embraced interactive mapping tools. A good recent example is the 2016 American Community Survey (ACS) State and County Dashboard. Here are a few reasons why I like the application:

  • It presents census data at both state and county level combining the big picture view with local detailed information.
  • It includes a rich set of vital census statistics that support a wide range of common use cases. The fact that they include median values instead of averages shows they are statisticians!
  • It shows a color gradient map of a selected statistic alongside its value in comparison to state and national values. Much better than a pop-up window!

Wrapping Up

One could debate whether Kenya’s 2009 census data are accessible, accurate or relevant, but it is obvious that population data from 2009 have limited value in 2018. Annual updates to the official census would be of great help in development planning and resource allocation.

Web mapping applications offer a great way of enhancing the dissemination and utilization of census data and KNBS ought to adopt interactive mapping and other visualization tools to unlock the statistical information contained in voluminous reports and tables. It would be of great benefit to the Kenyan people and economy.

About Author:

Willy Simons came to Kenya from The Netherlands in 1994. He is a serial entrepreneur and co-founder of Oakar Services, Esri Eastern Africa and Spatiality. He blogs about business, geospatial technology and cloud computing.