Do Marriage rate (UN) and Women's age at first marriage go together across countries?

Across 40 countries the link before adjusting for anything is r = -0.37, on a scale from -1 (opposite) to +1 (in step). A version that uses only each country's rank gives -0.30.

Does the link hold within countries over time, not just across countries?

Comparing each country only with itself across 2013-2021, and setting aside what happened worldwide in each year, the link is -0.015 (32 countries, 244 country-years). Using year-to-year changes, it is +0.074.

Does Marriage rate (UN) cause Women's age at first marriage?

This analysis cannot answer that. It shows only that the two go together. A link between two country measures, adjusted or not, does not show that either one changes the other. Country figures also say nothing about individual people.

Marriage rate (UN) vs. Women's age at first marriage

Holds up after adjusting for income

Across 40 countries, Marriage rate (UN) and Women's age at first marriage rise and fall together at r = -0.37 (on a scale from −1 to +1, where 0 means no link). It holds up almost unchanged when only countries with similar income (GDP per person) are compared (r = -0.43, q = 0.011, allowing for the many pairs tested).

Comparing countries across the middle half of women's age at first marriage, 28.9 to 32 years, marriage rate (un) is 0.487 marriages per 1,000 people lower at the top of that range than the bottom. Comparing only countries with similar national income, the gap is 0.631 marriages per 1,000 people.

Link before adjusting (r)-0.372p = 0.018 · 40 countries

After adjusting for national income-0.428p = 0.007 · likely range [-0.65, -0.13]

p, allowing for regions0.005standard error 0.078 · 5 regions

Check for luck (q)0.011across 12,497 pairs

How to read these.r runs from −1 (one goes up as the other goes down) to +1 (they rise together), and 0 means no link. Adjusting for national income means comparing countries with the same GDP per person, so differences in wealth can’t explain the link. Income is used in percentage terms, since an extra $1,000 means more to a poor country than to a rich one. p is how likely a link this strong would be if there were really none. Below 0.05 means it is unlikely to be chance. Very small values are written in short form: 1.1e-32 means a decimal point followed by 31 zeros and then 11, so very close to zero. The likely range is where the true figure probably lies, and a range that crosses zero means the link could easily be chance. Countries in the same region tend to resemble each other, so the third figure allows for that, which gives a fairer p. The standard error is the typical size of the error in r. Finally, testing this many pairs means some will look strong by luck alone. A q below 0.05 means this link is unlikely to be one of those.

Marriage rate (UN) · marriages per 1,000 peoplelink with income -0.21 · independent

Women's age at first marriage · yearslink with income +0.53 · moderate

“Link with income” is how closely each measure tracks GDP per person across countries, from −1 to +1.

Every country as a dot

best-fit line line after adjusting

Four ways to measure the link

Method	r	p	Countries
Standard (Pearson), not adjusted	-0.372	0.018	40
By rank (Spearman), not adjusted	-0.302	0.058	40
Standard (Pearson), adjusted for national income	-0.428	0.007	40
By rank (Spearman), adjusted for national income	-0.405	0.011	40

The rank version uses only each country’s place in line, from lowest to highest, so a few extreme countries count for less. The adjusted and unadjusted versions use the same 40 countries: those that report both measures and GDP per person. So the gap between them comes from the adjustment, not from a change in which countries are counted. Drop in the size of r after adjusting: -0.055 (a minus sign means it grew).

How solid is it?

Leaving out one country at a time, r ranges from -0.486 (without CAN) to -0.336 (without TUR). The bar above shows that range on a scale from −1 to +1, with the solid line at the full result. The single country that moves r most: TUR (+0.091).

Within each region

Countries are not separate, unrelated cases, and neighbors share a lot. A link that holds inside each region is far more believable than one that shows up only when comparing regions.

	n	r
Europe & Central Asia	30	-0.42

By income third

If the link shows up only in the richest third of countries, it is a feature of rich countries, not a general pattern.

	n	r
Poorest third	14	-0.57
Middle third	13	-0.29
Richest third	13	-0.35

By largest religious group

Countries grouped by a label they share, such as main religion, rather than by a number. Groups of fewer than twelve countries are not shown. These groups differ in income, region and history all at once. So a gap between them is a place to start asking questions, not an answer.

	n	r
Christians	33	-0.32

Without outliers (countries far outside the middle half of countries on either measure, by more than one and a half times the width of that middle half): r = -0.320 after dropping 2 countries.

Two series, one country

Both measures over the years for one country you pick. The two charts are stacked so they share only the years along the bottom.

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Over time, within countries

Everything above compares countries with each other at one moment. This section compares each country only with itself over 9years. So a link here can’t come from anything about a country that stays the same, such as its history, geography, institutions or culture.

Within countries over time, there is no link that is clearly more than chance (r = -0.015, comparing each country only with itself over the years, and each year only with the same year elsewhere). Whatever the cross-country picture shows, countries whose marriage rate (un) moved did not tend to see their women's age at first marriage move with it.

Across countries (adjusted)-0.428for comparison

Within countries-0.308each country vs itself

…and vs the same year elsewhere-0.015q = 0.957 · 32 countries

Year-on-year changes+0.074q = 0.768

Read with care.

Almost all of this indicator's variation is between countries, not within them, so the within-country estimate rests on a small part of the data.
Much of the within-country association disappears once shared global year effects are removed, which points to a common worldwide trend rather than a country-level relationship.

244 country-years (one country in one year), 32 countries, 2013–2021, about 8 years each on average. Share of the variation that happens within countries over time: 6% for Marriage rate (UN), 18% for Women's age at first marriage. The margins of error allow for each country appearing many times, and for each year’s value being close to the year before.

Year-to-year changes are a cautious test, not a final answer. Looking only at changes from one year to the next removes each country’s own trends. But it also makes measurement mistakes louder, which pulls the results toward zero. A near-zero result here is weak evidence of no link, not proof.

With one measure years behind the other

Same year (lag 0): -0.015. A peak away from zero does not show which comes first. These series change slowly — this year’s value is close to last year’s. That makes the curve smooth and nearly symmetric, whatever produced the data. Even a sharp peak at one lag (a gap of some years) would not prove that one measure changes the other.

The largest value on this curve (+0.21 at lag -8) is higher than the same-year one by 0.20. That gap is not a finding. It is the largest of 12 closely related estimates, and picking the biggest of many tests always makes it look bigger. That is exactly why nothing on this site is ranked or chosen by lag.

The data

	marriages per 1,000 people	years	Years
Turkiye TUR	6.65	25.2	2024, 2020
United States USA	6.1	28.6	2023, 2021
Denmark DNK	5.51	33	2024, 2020
Latvia LVA	5.45	29.8	2024, 2020
Romania ROU	5.32	27.3	2024, 2020
Iceland ISL	5.05	32.4	2020, 2011
Austria AUT	5	32	2024, 2019
Israel ISR	4.9	24.9	2023, 2019
Slovak Republic SVK	4.88	28.8	2023, 2020
Hungary HUN	4.86	29.5	2024, 2020
Estonia EST	4.63	29.9	2024, 2018
Lithuania LTU	4.47	28.4	2024, 2020
Croatia HRV	4.46	28.7	2024, 2020
Australia AUS	4.44	29.2	2023, 2020
Korea, Rep. KOR	4.36	30.8	2024, 2020

United Nations Statistics Division, Demographic Yearbook, 2017 to 2024 editions: tables of marriages and crude marriage rates, and of divorces and crude divorce rates, by urban/rural residence.
OECD databases as named on each indicator: PISA, Social Expenditure Database (SOCX), Income Distribution Database, Development Assistance Committee statistics, Family Database, Government at a Glance, Corporate Tax Statistics, employment and environment statistics

Sources

Marriage rate (UN)

Crude marriage rate, countries with complete registration

United Nations Statistics Division · UNdata terms of use · updated annual (each edition covers the latest five years)

Marriages registered in the year per 1,000 people, from each country's civil register, as published in the UN Demographic Yearbook. Only countries whose register the UN rates as at least 90% complete are included. That leaves out most of Africa and much of South Asia, where many marriages are religious or customary and never registered, so the countries here lean toward places with strong record-keeping. Countries whose figures include visitors' weddings (Seychelles, about 30 per 1,000, and the Bahamas) are left out, since they show a wedding industry rather than how often residents marry. So is Equatorial Guinea, whose register is far too thin to be complete. Each yearly edition covers five years; where they overlap, the newest is used, since countries revise. Where both exist it matches the OECD series almost exactly (r = 0.998), so the two are treated as one measure, not two findings. The low points in 2020 are the pandemic. A few small island territories, such as the Turks and Caicos Islands (11 to 16 per 1,000), probably count visitors' weddings without saying so. No "better" direction is set: it describes how people live.

Women's age at first marriage

Mean age of women at first marriage

OECD · via Our World in Data · CC BY 4.0 (OECD terms and conditions) · updated annual, except the snapshots noted per indicator

Published from 2001. How many countries report it varies from year to year: 25 in 2012, two in 2021. So the latest value in the time window used is from a different year for different countries. No "better" direction is set.

How this was computed

Data used: most recent value in 2010-2025; values come from 2011–2024. To adjust for income, each measure is first predicted from GDP per person (in percentage terms, on a log scale) with a straight-line fit. Only what is left over is then compared. This is called a partial correlation. The line is drawn the standard way (ordinary least squares), which picks the line that comes closest to all the countries at once. The error margins allow for countries in the same region resembling each other, using 5 World Bank regions. The q-value corrects for testing all 12,497 pairs at once, using the Benjamini–Hochberg method. Underlying data last updated DYB 2024. How the country data works · explore Marriage rate (UN) and Women's age at first marriage

This page shows that two measures go together. It does not show that Marriage rate (UN) changes Women's age at first marriage, or the reverse. These figures also describe countries, not individual people. See the ecological fallacy.