UK Total Coverage Now Almost 85%
The quality of OpenStreetMap (OSM) data just continues to grow and improve. Some statistics taken from the ITO! website, which compares OSM data to that of the national mapping agency (Ordnance Survey), shows 54 out of 408 local authority areas to be “complete”. This represents 13.2 percent coverage that is complete – at least on the measurement that ITO! uses for completeness. More than 39% of local authority areas are greater than 95% complete. 48.5% of local authorities are greater than 90% complete (198/408) whilst 66.4% have greater than 80% coverage today (these statistics are constantly being updated as changes get added to the OSM map); this is 271 local authorities.
At the other end of the scale there are only five local authorities where coverage remains at less than 50% of the district with the worst performer, Ryedale, having just 44.4% coverage. There is a northern dimension that comes into play here: of the five they are all in the North or the Midlands (they are Ryedale, Hambledon, Rossendale, Melton and Mansfield). Coverage for Wales and Scotland is looking very good with many authorities in these areas reaching 100%. Perhaps this is an indication of where the mapping community is not at its strongest?
26 Months ’til Completion?
The country summaries give some interesting metrics about the rate of change and the overall numbers involved in the open source mapping of just one country (the UK). There are a total of 853,993 road in OS Locator. There are 129,070 roads missing and 4,628 roads that minor errors such as St Chad’s Road compared with St Chads Road for example. Over the last month there have been an addition of 5,168 roads. At this rate will OpenStreetMap roads be completed in 26 months in the UK?
The methodology employed by ITO! takes OS Locator data and uses a bounding box to identify the extent of a road. Full details can be obtained from this blog post. The application can also show where errors or perhaps deliberate mistakes have been added to Ordnance Survey data. This almost extends the power of the tool away from an aid to help the OpenStreetMap project to one that can identify errors in OS Locator data.