Eurostat

Eurostat is the European Union's official statistics office, and its catalogue runs to thousands of datasets covering the economy, jobs, population, migration, trade, energy, farming, health, and the environment. The quiet superpower is harmonisation: national figures are reworked into comparable series, so a regional unemployment rate in Portugal genuinely lines up against one in Poland. Many series run back years or decades and break down by country, region (down to fine-grained NUTS levels), age, sex, and other dimensions.

Almost all of it is numeric tables rather than sentences, which changes how you feed it to a retriever. You can query the REST API, which hands back JSON-stat or SDMX (a standard format for exchanging official statistics), grab whole tables in bulk, or explore the online Data Browser. The pattern that works well for RAG is to render each table, or each meaningful slice, into short factual sentences ("In 2023, X in country Y was Z") and embed those, so plain questions land on text a spreadsheet cannot answer directly.

It is the source to reach for when you need trustworthy, comparable European numbers: policy research, economic dashboards, fact-checking, or any assistant fielding "how many", "how much", and "how does this country compare" questions. Being official and refreshed on a regular schedule, it makes a dependable grounding layer.

The caveats are practical rather than legal. Dimensions and units are coded and need decoding before they read naturally, provisional values get revised later, and definitions or coverage occasionally shift between years, so always keep the reference period and any quality flags attached to each figure. Reuse is authorised under Commission Decision 2011/833/EU for both commercial and non-commercial purposes, but you must credit Eurostat as the source.

It pairs neatly with OECD and World Bank data when you need reach beyond Europe, and with EUR-Lex when a question straddles EU law and the numbers behind it.