Estimates are prepared once a year for all countries, areas and territiories and are updated on the website after the estimation process is finished.
|
The methodology applied to arrive at the complete and consistent set of time series of main national accounts aggregates and their related growth rates and index numbers is as follows: annual collections of the national accounts statistics reported to the United Nations Statistics Division by the countries in form of the National Accounts Questionnaires are supplemented by estimates based on data and proxy economic indicators derived from national and international sources.
|
The sequence or priority of data sources sought to supplement reported data is as follows:
|
| - | Publications or internet websites of National Statistical Offices; |
| - | Publications or internet websites of Central banks or relevant government ministries; |
| - | Economic surveys and estimates prepared by the Economic Commissions of the United Nations; |
| - | Estimates and indicators available from other international organizations such as the International Monetary Fund (IMF), the World Bank and other international institutions; |
| - | Studies prepared by experts under the United Nations technical cooperation programmes; |
| - | Economic reports and studies by regional development banks. |
For a majority of countries, both the national accounts statistics reported by the countries and the proxy indicators may be based on different series due to multiple data configurations and/or characteristics. Before merging these into one data file, all inconsistencies in series and coverages are smoothed out by linking the multiple series into one homogeneous set of data from which the analytical measures are derived.
|
The current and constant price series are converted into US Dollars by applying the corresponding exchange rates as reported by the IMF. These are annual period-averages of the exchange rates communicated to the IMF by the monetary authority of each member country. The IMF distinguishes between the following three categories of exchange rates:
|
| - | market rates, largely determined by market forces; |
| - | official rates, determined by government authorities; and |
| - | principal rates, for countries maintaining multiple exchange rates arrangements. |
The preference is always market rates, only when these are not available other rates are used.
|
For countries not reported by the IMF, the exchange rates used are the annual average of United Nations operational rates of exchange which were established for accounting purposes and which are applied in official transactions of the United Nations with these countries. These exchange rates are based on official, commercial and/or tourist rates of exchange.
|
A major cause of excessive fluctuations and distortions of GDP data converted to US Dollars is high rates of inflation not fully reflected in exchange rate changes. In order to provide a more realistic conversion rate, the United Nations Statistics Division developed the price-adjusted rates of exchange (PARE) as an alternative to the exchange rates reported by the IMF or UN operational rates of exchange in cases where these would cause unrealistic results. The PARE methodology is aimed at eliminating these distorting effects of uneven price changes that are not well reflected in exchange rates and that yield unreasonable levels of GDP expressed in US Dollars.
|
It should be noted that the international comparability of data expressed in US Dollars between countries may not be entirely justified because the exchange rates applied may, in practice, only be used for the conversion of a limited number of external transactions and may not be relevant for the much larger portion of GDP covering domestic transactions.
|
