London boasts one of the best designed, not to mention most expensive, transport systems in the world – but even that is far from perfect. tool developed by George Walker at The Information Lab looks at how London’s public bus system can be used to examine the city’s social inequality. Walker, a trainee at The Information Lab, compiled data from 600 different bus routes that drive through the inner and outer boroughs of London and used that data to develop a tool depicting the discrepancies in average household income between richer and poorer areas of the city. Walker says he put the tool together in an attempt to visualize how income varies across the neighborhoods that London’s public buses move between on their daily routes.

In the years following the 2008 global economic crisis, the United Kingdom saw a relatively steady increase in the cost of living, specifically in London. A 2016 study conducted by the Center for London found that between 2012 and 2015, the cost of living in inner London increased from approximately £300,000 to more than £500,000 and further out from the center from approximately £280,000 to £380,000.

Walker’s tool, which can be adapted to any of the 600 bus routes he gathered data on, creates what can be considered a graph of inequality. On bus route six, the highest income, at £176,00 was in the area around the London Hilton Hotel stop, while the lowest was £36,000 in the area around the Bertie Road stop. The income disparity between these two areas, both of which the route six bus drives through, is a staggering £140,000.

public bus

Map of London’s five boroughs (CC: Centre for London)

Today, there are about 10,000 buses running 700 routes daily in greater London. Between the years 2014 and 2015, 2.4 billion Londoners used the bus to get around the city. Despite the importance of the public buses to London’s transport system, Tom Colthorpe, who also works with at the Centre for London, says the number of bus riders has been declining since 2014. In the face of hybrid bus-hire services and the increase in cyclists, Colthorpe says the number of bus riders in the 2016-2017 is expected to fall by 2.6%.

This is not to neglect the city’s attempt to encourage Londoners to use the bus. In September 2016, Mayor of London Sadiq Khan introduced what he called the one-hour “Hopper Fare,” which gives passengers a free bus ride within an hour after their first ride. The strategy aims to reduce the costs of running buses around the city by encouraging passengers to speed up their commutes. In 2018, a revised strategy will be released, giving passengers unlimited trips after their first bus ride. Although the Hopper Fare was used by 100 million passengers in its first year, Colthorpe believes that the net increase will be much lower compared to the 2.2 billion bus journeys made in a year.

public bus

CC: Aron Van de Pol

The move away from public buses as an efficient and practical means of transportation is not unique to London, however – the trend has been observed in cities across the U.S. as well. However, the majority of bus riders in the Greater London area come from low-income houses, leaving them with few other options for transportation.

Alongside Khan’s “Hopper Fare,” the city is planning on introducing what they’re calling the “Black Bus,” which will cover shorter routes based on demand. But as efficient as this measure may be on paper, what does this mean for bus riders? While the costs of taking the and running the bus system may decrease, city authorities could potentially drop certain bus routes altogether as a response to the declining numbers of bus riders.