What the data is telling us

Here are some visualizations of our data. The data covers only a portion of rail projects in each city/country and, in many instances, is not representative of all the lines constructed in that city/country. Similarly, Phase information refers to the number of phases of a project that we have cost information for, and therefore, is represented in our database. A project may have more phases in reality.

You can zoom in/out and hover over markers to see more detail.

1. Cost/km to Length of line

In this chart, each circle represents a project, and its color gradient represents the percentage that is tunneled.
We expect longer lines to cost less per km which is apparent for the outliers in the visualization.
New York’s East Side Access along with other New York, Hong Kong and Singapore lines are clear outliers with very high costs. Paris’ GPX and the Mecca Metro are the longest projects in our database, which also have lower costs per km.

2. Cost/km to Length of line (colors represent regions)

This chart is similar to the one above. Additionally, each color represents a region, which shows how costs vary by world region.
European projects (represented in blue), for instance, tend to be shorter and less expensive. Northern American projects (represented in green), on the other hand, are short and generally more expensive than European projects. East Asian projects (orange) tend to be less expensive independent of their length.

3. Cost/km, projects grouped for each country, in order of the cost based on the cheapest line

Here, we see the range of costs within each country, and the colors show the tunnel percentage for each project.
Even though China has the cheapest project, its most expensive one, Shanghai Line 1, is similar in cost/km to some of the most expensive countries in the database, those of Singapore and Qatar. The United States has the most expensive project in the database, its cheapest, the Miami Metrorail extension to MIA, falls below the mid-range costs/km in our database. However, this line, is 100% at grade.
We also see that the cheapest 100% tunnel projects in our database are Lyon’s Line A to Vaulx and Seoul’s Gimpo Urban Railway. The most expensive at grade line, on the other hand, is Hong Kong’s Tuen Mun South Extension.

4. Average Cost/km per Country

Here are all countries ordered by costs, based on the weighted average cost of the projects in on our database. The colors represent the weighted average of percentage of tunnel for the projects in each country, and the number of projects our database covers per country can be seen by hovering over each bar.
We see that Bahrain’s costs are on the lower end based on the two projects we have in our database, but they do not have tunnels. Malaysia, Egypt and UAE have the highest costs among countries that do not build a lot of tunnels.

5. Average Cost/km per Country and GDP (2017 adjusted for PPP)

In this chart, each country is represented with a circle, and the bigger the circle, the greater the number of projects in our database. Colors represent regions.
We use the World Bank’s numbers for GDP adjusted for PPP: https://data.worldbank.org/indicator/NY.GDP.PCAP.PP.CD
We see that there isn’t an obvious correlation between GDP per capita and costs. The US has high costs with one of the highest GDPs per capita, but countries like Norway and Switzerland have higher GDPs per capita and have much lower costs. We also see countries with low GDPs per capita building projects for relatively high costs: Egypt, Bangladesh, Vietnam and Philippines.

6. Average Cost/km per Country and Duration of Construction per km

Here we explore how construction costs interact with construction speed. The US is expensive and slow, Germany is slow but relatively cheap. Qatar is expensive but fast. China and India, on average, are cheap and fast. Chinese projects, however, are much more likely to be tunneled than India’s.

7. The timeline of rail construction for countries

Here we see how much and for how long each country in our database has been building rail rapid transit projects. The start and end years of each project is marked with a circle on countries’ lines. Hover over the points to see more data.
The continuation of a line does not mean the country has ongoing rail construction throughout the years.

8. A Heat map of costs per country in years

This chart shows how costs per country have changed over time. Colors indicate the square root of the Cost/km in $ M.
Each square represents the start of one or more projects in that country, and if there is more than one, the cost is the weighted average of the projects that started that year. China and India have been constructing rapid rail transit continuously and for consistently lower costs. Countries like Turkey, Spain, South Korea and Bulgaria also build for consistently lower costs.