What the data is telling us

Most recent update: 02/27/2024

Here we present 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.

684 lines (broken down into 883 phases) from 59 countries and 187 cities from our database are represented in these charts. Total length of the projects is 19,792 kilometers, or 12,298 miles. The cost values are PPP and inflation adjusted for 2023.

The weighted average of cost/kilometers is $236.78 million and the weighted average of cost/miles is $381.07 million.

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 and Hong Kong lines are clear outliers with very high costs. Paris’ GPX is the longest project in our database, which also has a 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 20 Phase 1 at $571.6 million/kilometer, is close in cost/km to some of the most expensive countries in the database, those of Netherlands and United Kingdom. The United States has the most expensive project in the database, its cheapest, the Chicago Orange Line at $81 million/kilometer is within the cheapest lines in our database, however, this line is 100% at grade.
We also see that the cheapest 100% tunnel projects in our database are Catania’s Borgo-Nesima Line and Lyon’s Line A to Vaulx at $57.9 and $100.1 million/kilometer respectively. The most expensive at grade line, on the other hand, is Line 4 of Cairo at $813 million/kilometer.

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, UAE and the US have the highest costs among countries that do not build a lot of tunnels.

5. Average Cost/km per Country and GDP (2020 adjusted for PPP)

In this chart, each country is represented with a circle, and the bigger the circle, the longer the total length 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.

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

Here we explore how construction costs interact with construction speed. The projects with missing construction dates are omitted, only 629 records are included. Note that the average cost/km for countries might have changed due to this omission.

The Netherlands’ one project, the North-South Line in Amsterdam, is slow; the US is generally expensive and slow. China and India, on average, are cheap and fast, but Chinese projects in our database are often so recent their completion year is subject to change. But as a note of caution, a handful of items on our list are multi-phase networks, in which case the duration of construction looks longer than it is; Qatar is one such example, and in fact from groundbreaking to first phase opening, the Doha Metro, while still very expensive, only took six years, not 13.

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.

As in the above chart, the projects with missing construction dates are omitted.

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. Countries like Turkey, Spain, South Korea and Bulgaria have been building rail for consistently lower costs. China and India show lower to median costs. Italy’s costs on the other hand, show a descending trend over the years.