Common Ground Between North and South Korea: Aging and Shrinking Populations

By Matt Stiles | | Topics: Demographics, North Korea, South Korea

The birth rate in South Korea, where I live and work, hit a record low this year, leading to concern about the impact an aging (and, eventually, shrinking) population might have on the nation’s society and economy.

These charts show the long-term trends, both in actual population and projected changes, according to United Nations data. I’ve added North Korea, which actually has a higher fertility rate today, for context.

First, let’s look at the populations of the two countries, which share an ethnic background and a (mostly) common language — despite the Korean War-era division of the peninsula.

South Korea has about 51 million residents, roughly twice the number of people in the North, which has 25 million. That’s the number of South Koreans who love in the Seoul metro area, by the way.

Both populations are expected to peak in two decades — and then begin to decline.

That downward trend, for now, is much more pronounced in South Korea because of the nation’s low birth rate. Having a large family in South Korea, where housing and education costs are pricey, isn’t possible or practical for many people. The nation also has relatively weak maternity leave policies (and stubbornly traditional gender roles in the home and workplace), leading women to postpone childbirth to pursue their careers.

South Korea is slightly smaller geographically (about the size of Indiana, in terms of area) than the North (roughly the area of Pennsylvania). So their respective population densities vary, too:

Here’s how South Korea has grown, in five-year-increments, since 1950 — when the Korean War began and ultimately changed the trajectories for both countries. South Korea saw relatively rapid growth rate immediately after the war, perhaps as refugees resettled. Projections show that rate declining by 2035:

The North experienced a rapid decline during the war, mostly likely from the death toll during the conflict, the political purges that followed — and the southern migration before the border was secured. Its growth rate soon recovered, however, but could begin declining again by 2045.

Here’s hoping the Korean fertility rate rebounds, or the two nation’s unify — or either becomes more welcoming and accommodating of immigrants. At things stand now, South Korea could become “extinct” by 2750 — a worrying (though simplistic and imperfect) simulation for a uniquely homogenous society that traces its roots back thousands of years.

Mapping Opposition to the GOP Health Care Bill by Congressional District

By Matt Stiles | | Topics: Demographics, Policy & Politics

The legislative failure of the GOP’s replacement for Obamacare has been widely reported, obviously, but I remain interested in one bit of polling noted this week by FiveThirtyEight.

The polling firm YouGov estimated the legislation’s unpopularity by congressional district. The bill itself was quite unpopular, it turns out, even in conservative districts, as FiveThirtyEight’s Nate Silver reported.

Thanks to DailyKos Elections, we can also marry the data with President Donald Trump’s vote share in each district.

I’ve been experimenting with maps in D3.js, and I hadn’t yet tried congressional districts. So this seemed like a perfect opportunity, even if thematic maps aren’t particularly useful in this context (because congressional districts vary in size geographically, such maps can be misleading).

Case in point: The national map of congressional districts, with Republicans in red and Democrats in blue . As we all know, Democratic districts tend to be smaller in terms of area and clustered in more densely populated places. So they don’t get a particularly fair representation on a map:

Consider these two treemaps. This first shows members of the U.S. House by party (with some vacancies in gray). Shapes are sized based on the average population of each congressional district: roughly 710,000 people, give or take five percent. The House has 237 Republicans, 193 Democrats and five vacancies. There’s clearly a red majority, but it’s relatively close:

This treemap, however, shows the geographic area in square miles. Now you see the distortion:

OK, you get it. So let’s see how the health care opposition looks on maps.

Happy Valentine’s Day, America: Charting Our Declining Marriage Rate

By Matt Stiles | | Topics: Demographics, News

It’s Valentine’s Day, a perfect time to note that the marriage rate in the United States has been on a steady decline for decades, save for a brief spike in 2012.

So romantic.

Here’s the rate per 1,000 people since 1997:

You can also view that rate by state. What’s up with you, Hawaii? (I’ve excluded Nevada, which skewed the axes for all the small multiples because of its freewheeling marriage culture). There are some interesting trends here, but most states remain relatively close to the national rate:

Here’s the 2015 marriage rate, by state, on a tile grid map:

Mapping South Korea’s Total and Foreign Populations — by Municipal District

By Matt Stiles | | Topics: Demographics, South Korea

South Korea, my adopted home for almost two years, has about 50 million residents as of the last census, in 2015. Most of them are settled in the country’s urban areas. About 22 million residents, for example, live in Seoul, the capital in the country’s northwest corner, and its adjacent province, Gyeonggi.

As an experiment to create a choropleth map with D3 and NPR’s dailygraphics rig, which drives most of the visualizations here, I’ve mapped the total population by municipal districts. In this example, Seoul is outlined with red:

I am, of course, not a citizen of South Korea. I’m a “foreigner” — as we’re referred to here. This is where the 1.3 million foreigners — many of them ethnic Koreans who immigrated from China — have settled across the country. Again, Seoul is outlined with red:

And this map shows the roughly 330,000 foreigners living in Seoul proper. This time I’ve highlighted Yongsan-gu, my home district in the city center:

Mapping Where ‘Americans’ Live

By Matt Stiles | | Topics: Demographics, Policy & Politics

Back during the Republican primaries, The Upshot published an interesting short post called the Geography of Trumpism. The reporters back then analyzed hundreds of demographic variables, by county, in an effort to determine which ones might be predictive of electoral support for the eventual GOP nominee.

Think: What’s the rate of mobile home ownership? Or what percentage of people in a particular place have college degrees? They found a key variable to explore:

When the Census Bureau asks Americans about their ancestors, some respondents don’t give a standard answer like “English” or “German.” Instead, they simply answer “American.”

The places with high concentrations of these self-described Americans turn out to be the places Donald Trump’s presidential campaign has performed the strongest.

I’ve plotted the percentage of “American” ancestry, by county, on a national map. Keep in mind the data come from a five-year survey by the U.S. Census Bureau, so the accuracy in large counties is relatively safe.

But in smaller counties — say, those with fewer than 10,000 residents — the margins of error can be quite high. The results are even more problematic in the tiniest of counties. Still, this is the best public data we have, and it does produce some interesting geographic trends:

Charting American Birthdays: Yours Probably Isn’t That Special

By Matt Stiles | | Topics: Demographics, Policy & Politics

Last week I published a new heatmap exploring the popularity of American birthdays. The chart, which uses darker shades to represent higher average birth counts on specific days, can give the impression that some birthdays are much more common than others.

In reality, outside of some special occasions, namely major holidays, there isn’t a huge amount of diversity in the data set, which has two decades of births aggregated by day. Most birthdays, including my own, are fairly average — especially in the first six months of the year. For example:

How Common is Your Birthday? This Visualization Might Surprise You

By Matt Stiles | | Topics: Demographics, News

It’s baby season in America, with September the busiest month for births on average in the last two decades. So it seemed like the right time to remix this blog’s most-popular post: How Common is Your Birthday?

That old heatmap, which highlighted specific dates for popularity, has been viewed more than 500,000 times here and published across the web. But it was flawed, namely that it used ordinal data (birthday ranks by date) rather than continuous data (actual births counts by date). This graphic finally addresses that problem:

Visualizing World Alcohol Consumption: What Beverages Do Countries Prefer?

By Matt Stiles | | Topics: Demographics, South Korea

I posted recently about how countries consume different amounts of alcohol — and how some have wider gender gaps when it comes to booze.

The previous posts relied on two data sets from the World Health Organization, which calculates consumption (in liters and grams) based on surveys and actual import, exports and sales data. The organization, a reader noted recently, also breaks down the consumption totals proportionally by beverage.

This chart shows each country and its relative tastes for beer, wine, spirits and “other,” which, in South Korea at least, is mostly soju, a fermented rice beverage that’s not easily categorized.

Visualizing World Alcohol Consumption: How Much Does Each Country Drink?

By Matt Stiles | | Topics: Demographics, South Korea

A few weeks ago I posted about gender gaps in alcohol consumption around the world.

In some countries — South Korea, for example — men and women consume quite different amounts of booze, according to the World Health Organization. Fueled by a love for soju, South Korea’s men are among the heaviest drinkers in the world, consuming about 78 grams per day — nearly twice as much as other men on average. Its women drink only slightly more than their counterparts abroad, on average.

But that data only averaged daily consumption, by country, among people who list themselves as “drinkers”. The organization also has estimates about per-capita consumption amounts based on countries’ import, export and sales data, normalized with their adult populations. Depending on your question, that might be more useful information.

Those data, which also offer a breakdown of alcohol types (beer, wine, spirits and “other”), tell a different story. Instead of leading the world, by that measure South Koreans rank farther down a list of 196 countries: 35th.

Are People in Colder Countries Taller? (Continued…)

By Matt Stiles | | Topics: Demographics, Weather

Earlier this week I posted two scatterplots examining the relationship between a country’s average temperature and its male residents’ average height. The data show some correlation, but there probably are several of other factors affecting height as well.

The earlier plots shaded the country dots by income and region, allowing more context about the groupings of countries (hint: Europe is colder and taller).

This next version, however, proportionally sizes the dots by population, adding another layer of context (or perhaps unnecessary complexity).