Data Graphics London

London’s Oyster Card Tidal Flow

Here is an animation I created a couple of years ago, one of a number I created for the “Sense and the City” exhibition at the London Transport Museum, which ran from Summer 2011 to Spring 2012. A version of this animation was branded appropriately for the exhibition and shown upstairs in the interactive section. I also created a similar animation of the Barclays Cycle Hire, and colleagues created other map-based visualisations of the moving city.

The animated map shows the touch-ins (going into the network) and touch-outs (leaving the network) of Oyster cards at London’s tube and train stations, including a few beyond the Greater London boundary which still accept Oyster cards. Oyster cards are London’s travel smartcards. As the animation moves forwards in 10-minute intervals during the typical weekday, the balance between touch-ins and touch-outs is shown by a colour scale. Red indicates the great majority of taps are touch-ins, and green indicates mainly touch-outs. White is the “neutral” colour, indicating that roughly as many people are entering the network as leaving it, at that period in time.

17 replies on “London’s Oyster Card Tidal Flow”

The opacity shouldn’t change – only the hue. I use a set opacity of less than 100% to allow data underneath to “shine through”.

I believe the TfL developer area webpage has a 5% Oyster Card sample from a week in 2009 – it’s not quite as comprehensive as the data that was used for this animation (which is a 100% feed for one day in early 2011) which was supplied especially to us from the Transport Museum for their exhibition (and so probably not shareable I’m afraid), but essentially it’s the same data. It will need some tidying and possibly geocoding of the stations first though. There is another datafile on the same page which has geocoded station locations – but only of TfL stations, not the regular railway stations which also use Oyster for (some) journeys.

Probably much more interesting is a third datafile on that page, which is newer (from early 2011), and has passenger counts for all underground stations, in 15 minute intervals – i.e. almost as granular as used for this animation (which is every 10 minutes) – however it only includes underground, not railway stations.

Pretty nice visualization. I would love to get my hands on London tube data; so many ways to slice and dice it!

Anyways, I think there were a couple of pieces of information that have been left out. One, how are the sizes of the circles determined? Is it by total number of in and out swipes, total number of station swipes, total number of station swipes as a percentage of all mapped swipes? And two, what is the time frame of the data collected? Is it some random Monday through Friday? Or is it the average of all the Monday through Fridays over a given time (like during the spring or a month in the summer)?


The areas of the circles (not radii) are directly proportional to the absolute number of taps (in+out) in each 10-minute interval. The data is from a single day – indeed you can see individual trains loading/emptying on some quiet parts of the network, e.g. Chesham, because they get less than one train every 10 minutes during some parts of the day. I think it was a Tuesday, Wednesday or Thursday in early 2011 but I can’t remember beyond that I’m afraid. I generally avoid using Mondays and Fridays because of weekend edge effects – much more pronounced for the bikeshare data I normally study/visualise but still a possible effect here.

p.s. For more details on getting data similar to this see my response to the comment below.

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