2010 to present: All data are taken from Eurostat.
1999 to 2010: Euro area GDP (constant price and seasonally adjusted), investment (gross fixed capital formation, constant price and seasonally adjusted) and industrial production (seasonally adjusted) series are from Eurostat. Euro area employment is the index published by OECD (Main Economic Indicators; calculation from labour force sample surveys ) Large countries' GDPs are from Eurostat (constant price and seasonally adjusted).
For the US we use Real Gross Domestic Product [Billions of chained (1996) dollars] Seasonally adjusted at annual rates, Table 1.2., Line 1, Bureau of Economic Analysis. Gross private domestic investment [Billions of chained (1996) dollars] Seasonally adjusted at annual rates, Table 1.2., Line 6, Bureau of Economic Analysis. Employment: Total Non-farm Employment - Seasonally Adjusted, Bureau of Labour Statistics Industrial Production, NBER website.
1970-1998: Euro area GDP, investment and employment are from the data set constructed at the ECB by Fagan et al. (FHM). This data set includes national account data and labour market data. We also use GDP statistics from OECD Quarterly National Accounts Database (Gross domestic product /GDP by Expenditure, Comparable Table /Constant prices, constant PPPs, OECD base, annual rates SA).
For large countries the sources are OECD Quarterly National Accounts (QNA), Main Economic Indicators (MEI) and Quarterly Labour Force Statistics (QLF):
Gross domestic product /GDP by Expenditure, Comparable Table /Volume index, OECD base, SA /1995=100. Source: QNA.
Gross fixed capital formation /GDP by Expenditure, Comparable Table /Volume index, OECD base, SA /1995=100. Source: QNA.
Civilian employment index sa/Index publication base SA /Civilian Employment (survey)All persons/Levels/All ages. Source: QLF.
Industrial production ISIC C-E sa/Index publication base SA /Production/Production by economic activity /1995Y. Source: MEI.
The only exception is GDP for Germany. Since the OECD series starts only after reunification, we use statistics from the IMF (GDP Gdp Vol. (1995=100) /Index Number /Base year: 1995 /averages /constant prices).