The calculation of global trade Total Value or global trade Total Value in a product can be achieved by aggregating the Total Value of all Countries or Economies involved in international trade or the Total Value of all Countries or Economies involved in international trade in a product. However, in practice, due to differences in the speed of data aggregation by national official statistical agencies, at a certain point in time, the progress of updating statistics on trade in goods varies from country to country, which makes the global trade Total Value measured by the simple aggregation do not have data consistency. This can be understood as follows: Assuming that at time point A, 205 of the 205 reporting countries carried by the system have completed data updates, and at time point B one month in the future from time point A, only 150 of the 205 reporting countries carried by the system have completed data updates, so when the simple aggregation method is used to calculate the global trade Total Value, there will be an undesirable difference in the statistical scope of the Total Value at two points in time. In order to avoid the above problems and at the same time obtain an accurate and reliable global trade Total Value, the system selects 137 Countries or Economies with stable and consistent updating progress as the aggregate scope of the statistics, and adopts the mirroring method to fill in the data of non-major economies that have not yet been updated at some recent points in time. The global trade Total Value from this methodology is the Applied Total Value. It has been calculated that the Applied Total Value can be accurately updated to the two months before the current point in time and can consistently total more than 97% of the theoretical global trade Total Value, with data consistency and analytical validity. The General Administration of Customs of the People's Republic of China has adopted this Total Value as the standard Total Value for global measurement.

" The calculation of global trade Total Value or global trade Total Value in a product can be achieved by aggregating the Total Value of all Countries or Economies involved in international trade or the Total Value of all Countries or Economies involved in international trade in a product." The global trade Total Value calculated by this method is the Total Global Value, which is used in this system by aggregating the Total Value of the 205 Countries or Economies carried by this system. There is an analysis curve for this Total Global Value in the global trade balance analysis dimension. The measured historical trend of this total is consistent with the basic judgment of the historical trend of total global trade, but in the historical 12 years of data, the annual total exports usually exceed the annual total exports of WTO statistics ranging from 500 to 1,000 billion USD.

The Displayed Total Value is the Total Value of the analysis scope shown in the visualization chart, while the Applied Total Value is the Total Value applied in the calculation of each share in this analysis dimension. The statistical method of the Applied Total Value can be found in the " Statistical methods and limitations of global trade Total Value and Applied Total Value ". Since the scope of the reporting country's statistics may include unspecified partner countries or partner countries that are not part of the normal economy, there may be a difference between the Displayed Total Value and the Applied Total Value in the system's analysis, with the Displayed Total Value usually equal to or slightly less than the Applied Total Value.

HS Code is the customs code, the full name is the International Convention for Harmonized Commodity Description and Coding System, referred to as the Harmonized System (abbreviated as HS). The HS Code was developed under the auspices of the World Customs Organization. It was officially implemented on January 1, 1988 and is revised every five years. The system is a scientific and systematic international trade commodity classification system, applicable to tax rules, statistics, production, transportation, trade control, inspection and quarantine, etc., and is used by all countries in the world. The HS Code divides all international trade commodities into 22 categories (major categories of commodities) and 98 chapters (each major category covers several chapters). The first and second digits of the HS Code represent "chapter", the third and fourth digits represent "item", and the fifth and sixth digits represent "sub-item". The first 6 digits are the HS international standard code (HS2/4/6 is common in all countries). Some countries further subdivide the seventh, eighth, ninth, and tenth digit codes according to their own actual conditions to accommodate more subdivided product categories and specifications. Countries differ. The HS Code is currently revised to the 2022 version. The statistical caliber of this system includes the 2007 version, the 2012 version, the 2017 version and the 2022 version of the HS Code.

SITC, known as Standard International Trade Classification, is a standardized classification method dedicated to statistics and comparisons of internationally traded goods. Its development can be traced back to the first half of the 20th century. In 1920, the League of Nations was established and began to formulate international trade terminology and commodity statistical catalogs. The League of Nations published the "Draft of Tariff Terms" in the 1930s, and based on this draft, it was revised into the "Compendium of International Trade Statistics Commodity Catalog" used by all member countries. After the end of World War II, 51 countries jointly founded the United Nations. In order to conduct unified statistics and analysis of world trade, the United Nations Statistics Division further revised the compendium of the above-mentioned commodity catalog, and formulated the "Standard International Trade Classification", or SITC Code, in 1950. SITC Codes are divided into 10 categories, 50 major categories, 150 medium categories and 570 subcategories. It serves as a common basis for various international organizations to make trade statistics reports and conduct systematic analysis of world trade. This standard was recommended to member states by the United Nations Economic and Social Council in 1951. The "Standard International Trade Classification" has been revised several times since it was promulgated and implemented in 1951. Except for the category framework, other categories have also expanded with the increase in levels.

The following is excerpted from the International Trade Statistics Branch of the United Nations Statistics Division:
"Used to compile international trade statistics for all goods entering international trade and to promote the international comparability of international trade statistics. SITC groupings of goods reflect (a) the materials used in production, (b) the stages of processing, (c) market practices and uses of the product, (d) the importance of the commodity in world trade, and (e) technological change" ("The United Nations Statistics Division" Standard International Trade Classification). The difference between HS Code and SITC Code is that HS Code is a standard code developed and maintained by the World Customs Organization and used by national customs for classification, supervision and statistics of import and export commodities, while SITC Code is developed and maintained by the United Nations Statistics Division for international trade statistics based on national economies. The international trade statistics are first compiled in HS Codes and then converted to SITC Codes through a code conversion table. The United Nations Statistics Division completed the last revision of the SITC Codes in 2006, which was the publication of SITC Rev.4. However, since SITC Rev.4 can only be converted to HS Codes from the 2007 edition and beyond, the world's mainstream trade statistics agencies and international economic and trade organizations such as the WTO continue to use SITC Rev.3 released in 1986 as the main statistical caliber. This system uses SITC Rev.3 as the statistical caliber.

Trade Balance = exports - imports. Generally speaking, a government should try to maintain a basic balance between imports and exports in foreign trade, with a slight surplus, which is conducive to the healthy development of the national economy. The trade surplus refers to the phenomenon that a country or region's exports are greater than its imports in a certain period of time, and the trade deficit refers to the phenomenon that a country or region's imports are greater than its exports in a certain period of time. At the same time, differences in statistical calibers may adversely affect the calculation of the trade balance.

A Reporter is the country or economy from which the data originates. The Visualization Lab includes 250 reporting countries or economies, with all data sourced from official national statistical agencies and international organizations, updated monthly.

Partner Countries or Economies are the trading partners of a country or economy. When choosing the export direction, the partner country or economy is the export destination country of the country or economy. When choosing the import direction, the partner country or economy is the import source country of the country or economy. This system accommodates a total of 250 single partner countries/economies (including the Kosovo region and the Netherlands San Andreas), including all Countries or Economies in the world.

In international trade statistics, due to the differences in statistical calibers and commodity packaging specifications between countries, there may be multiple quantitative statistical units for the same type of goods or the same commodity, such as kilograms (kg), number (No), liters (L), etc. And since the specifications and density of the product itself cannot be known, effective conversion of each unit cannot be performed. Therefore, this system adopts the method of counting quantities by units, and continues to use this method to count the unit price.

A Country Group is a group of countries considered as one country or economy for statistical purposes when the countries in the group are combined. It includes groups of countries divided by geographical regions, trade agreements, union countries and other special compositions.

Excluding internal trade of the Country Groups means: assuming that China, Japan, and South Korea are treated as a Country Group, and excluding Country Group internal trade means excluding China's trade data with Japan and South Korea, South Korea's trade data with China and Japan, and Japan's trade data with China and South Korea, and treating the Country Group as a single economy that is completely external to the outside world, then the total foreign trade of the China, Japan, and South Korea Country Group at this time is the total trade volume of China, Japan, and South Korea with other non-China, Japan, and South Korea Countries or Economies. In terms of research significance, excluding the internal trade of the Country Group can analyze the foreign trade partners or commodity composition of the Country Group more clearly, while not excluding the internal trade of the Country Group can analyze the trade volume of the Country Group, the internal trade of the Country Group and so on, which are useful in their own ways.

Dalian Infobank‘s Global Trade Statistics Database can be traced back to January 1985, and the latest data can be updated to the month before the current month of the current year. However, due to the inconsistency in the coverage of national data from various data sources, in order to ensure the global analysis of global trade and the completeness of the coverage of the countries in the analysis of the various structures as far as possible, January 2010 is selected as the starting point of the analysis, and the latest month of the update data is taken as the end point of the analysis.

Question: How to find out the imports and exports between Zimbabwe and China in 2021 when the statistics on Zimbabwe's imports and exports in 2021 are not available.
Answer: The total amount of commodities exported from China to Zimbabwe in 2021 can be equated to the total amount of commodities imported by Zimbabwe from China in 2021 without considering the difference in statistical caliber, and vice versa.
The data obtained for a particular time period for a particular country through the above logic is the mirrored data.
This system employs a mirroring method to make up for un-updated or missing data, and the specific coverage of the mirrored data can be found in the 'Data Dictionary'.

The statistical data on goods trade between China's provinces and special administrative regions only cover the trade of provinces and regions exporting to or importing from other countries, and do not include the trade between provinces and regions and other provinces and regions. The General Administration of Customs of China uses the method of locating the registration place of each importer and exporter when compiling statistics on trade in goods of each province in China. For example, if a company registered in Beijing exports a certain commodity to the United States, it will be recorded as a certain commodity exported from Beijing to the United States. At the same time, the trade statistics of Hong Kong Special Administrative Region, Macao Special Administrative Region and Taiwan Province are not compiled by the General Administration of Customs of China, but by the administrative units of the respective regions.

The Total Value of China (mainland) covers all provinces, municipalities and autonomous regions in mainland China, and the Total Value of China (including Hong Kong, Macao and Taiwan) covers all provinces, municipalities and autonomous regions in mainland China, Hong Kong Special Administrative Region, Macao Special Administrative Region and Taiwan Province.

The first 6 digits of the HS Code are the HS international standard code (HS2/4/6 is common in all countries). Some countries further subdivide the seventh, eighth, ninth, and tenth digit codes according to their own actual conditions to accommodate more subdivided product categories and specifications. Countries differ. The last digit code under the country refers to the HS Code extending from the 6 digits of the HS Code to the smallest commodity classification in each country. Dalian Infobank's global goods trade statistics database contains trade records of more than 100 major global trading Countries or Economies broken down to the last HS Code.

This system defines Chain Growth Rate as month-on-month growth rate, and year-on-year growth rate as compared to the same period last year.

Linear regression is a linear regression line fitted to the full time period data that does not vary with the time axis.

Move Aggregation calculates the cumulative total for each data line in the time axis range.