The CDS (the Common Data Set) is a joint effort by Eurostat, OECD, UNSD, UNCTAD and WTO to reconcile their time series on merchandise trade statistics, using international standards as a benchmark. Each agency is in charge of supplying figures for a predefined set of reporting economies (see Data Providing Agencies and Sources). Reconciliations, co-ordinated by WTO, consist of scrutinising significant differences between the agencies' data to determine the best value. In many instances, this results in finding an agreement on substitution values and estimates. Thus, the CDS database gives access to statistics and documentation of both officially reported and reconciled series. It covers annual total merchandise export and import values of over 200 economies for the period 1995 to 2011.