This annex contains data on key economic series which provide a background to the recent economic developments in the OECD area described in the main body of this report. Data for 2014 to 2016 are OECD estimates and projections. The data in some of the tables have been adjusted to conform to internationally agreed concepts and definitions in order to make them more comparable across countries, as well as consistent with historical data shown in other OECD publications. Regional aggregates are based on weights that change each period, with the weights depending on the series considered. For details on aggregation, see OECD Economic Outlook Sources and Methods.