Lecture 9 - The Economics of Immigration
1. Introduction: The Economics of Immigration
Immigration is presented as a controversial but central economic issue. The lecture explicitly commits to presenting both sides of the debate, reflecting the academic norm that citation does not imply endorsement.
Immigrant: A person born abroad residing in the host country.
Native: A person born in the host country.
The term is technical and not cultural or normative.
The lecture structure covers four pillars:
- Empirical facts about immigration, with a UK focus
- Labour market effects
- The migration decision
- Fiscal implications
These map directly onto the core economic questions of efficiency, distribution, incentives, and public finance.
Immigration is fundamentally about the movement of labour across borders. In a standard neoclassical framework, migration reallocates labour from low marginal product regions to high marginal product regions, increasing global output. However, distributional consequences within countries generate political tension.
2. Measuring Migration
Understanding migration begins with measurement. The lecture distinguishes three core measures:
Long-term immigration: Individuals moving to the UK for at least 12 months.
Net migration: Long-term immigration minus long-term emigration.
Visa grants: Administrative count of visas issued.
2.1 Why Measurement Is Difficult
Visa data are an imperfect proxy because:
- They exclude those not requiring visas.
- Policy changes alter who requires visas, affecting comparability over time.
This highlights an important empirical principle:
Do not treat administrative visa counts as equivalent to actual migration flows. Policy changes alter definitions.
2.2 Data Sources
The Office for National Statistics combines:
- Administrative tax and benefit data
- Border data
- International Passenger Survey data
Each source involves assumptions about intended vs actual duration of stay.
Measurement error introduces uncertainty into political debates. When migration estimates are revised, public trust may erode even if revisions reflect improved statistical methodology.
3. Net Migration Trends
The chart shows total immigration, total emigration, and net migration (2012–2025). Key moments include:
- The EU referendum
- The COVID-19 lockdown
- The new immigration system post EU transition
The most striking feature is the sharp post-2021 rise in immigration, particularly non-EU migration.
Immigration responds strongly to policy and macro shocks. Lockdowns suppressed mobility. Reopening plus new visa routes increased flows.
When discussing migration trends, reference structural breaks such as Brexit and COVID. Examiners reward linking data patterns to institutional change.
4. Immigrant Composition
This slide decomposes net migration into:
- Non-EU
- EU
- British nationals
Post-Brexit, EU migration declines sharply, while non-EU migration increases substantially.
Brexit represents a regime shift from free movement to a points-based system. The composition effect demonstrates how immigration policy affects who migrates, not necessarily just how many.
Policy restriction on EU free movement → reduction in EU inflows → substitution toward non-EU routes
5. Non-EU Migration by Motivation
This chart separates migration motives:
- Study-related
- Work-related
- Asylum
- Humanitarian
- Other
The large rise post-2021 is driven primarily by study and work routes, not asylum.
Universities act as major export industries. International students represent both migration flows and service exports.
Distinguish between economic migrants and asylum seekers. Public discourse often conflates categories.
6. Non-EU Migration by Country
The largest contributors include India, China, Pakistan, Nigeria and Nepal. Much of Indian and Chinese migration is study-related.
Human capital theory predicts migration flows from countries where expected returns to education are high abroad relative to home.
Higher UK wage premium for skilled labour → incentive for high-skill migration
7. Data Revisions
Initial estimates are revised substantially over time.
Treating provisional estimates as final. Migration data are subject to substantial revision.
This raises a broader issue: economic policy is often made under uncertainty.
8. Population Dynamics
Population change is defined as:
From 2004–2023, 65% of UK population growth came from net migration.
From 2020–2023, 98% came from net migration.
In ageing societies with fertility below replacement, migration becomes the dominant source of demographic growth.
Low birth rates reduce labour supply growth. Immigration offsets demographic decline.
The population chart shows net migration dominating annual change post-2021.
Stylised fact: recent UK population growth is almost entirely migration-driven.
9. Spatial Distribution
European map: foreign-born populations concentrate in major urban regions.
OECD evidence confirms migrants disproportionately settle in large metropolitan areas.
Agglomeration economies attract migrants. Cities offer higher wages, thicker labour markets, and migrant networks.
Urban wage premium + network effects → spatial concentration
10. Historical Perspective: The United States
Between 1882 and 1924, 26 million immigrants arrived in the US.
The long-run data show waves of immigration rather than a steady trend.
Migration responds to economic booms, wars, and policy restrictions. It is cyclical rather than linear.
11. Core Economic Issues
The lecture identifies key areas of debate:
- GDP effects
- Public finances
- Wage and employment impacts
- Migrant welfare
- Political and cultural concerns
In a competitive labour market model, immigration shifts labour supply rightward.
- Total output increases
- Wage effects depend on substitutability between migrants and natives
- Capital adjustment matters
12. Policy Questions
Three fundamental policy levers:
- Quantity: How many migrants?
- Composition: Which types?
- Rights: What entitlements post-arrival?
Structure essays around these three dimensions. It provides analytical clarity.
13. Public Attitudes
European Social Survey results show variation by education level in beliefs about wage effects.
Lower-educated respondents are more likely to agree immigration lowers wages.
Perceived labour market competition shapes attitudes. Individuals expecting substitution effects oppose immigration.
Perceived wage competition → anti-immigration attitudes
Key Takeaways
- Migration measurement is complex and frequently revised.
- Post-Brexit UK migration is predominantly non-EU and study/work driven.
- Population growth is now largely migration-dependent.
- Migrants concentrate in urban areas due to agglomeration effects.
- Public attitudes reflect perceived distributional impacts.
- Policy debates centre on quantity, composition, and rights.
Bibliography
Astruc, E., Le Souder, C. et al. (2024) Spatial distribution of migrants across Europe and the OECD.
Dustmann, C., Glitz, A. and Frattini, T. (2008) The labour market impact of immigration. European Social Survey evidence.
Office for National Statistics (2024) UK Migration Statistics.
US Department of Homeland Security (2023) Historical Immigration Data.
University of Nottingham (2026) ECON1016 Current Economic Issues L1 printable.