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5.12.1 Objectives and uses of the product
The overall objectives of AASS are:
(i)
To obtain basic data to be utilized in the preparation, formulation of policies and
implementation of agricultural plans at national and regional levels in between the
agricultural census years;
(ii)
To obtain time series data on agricultural production & productivity at national and
regional levels; and
(iii)
To obtain basic statistics for comparison on the development of the agriculture
sector in the country.
5.12.2 Methodology of data production Survey Organization The Annual Agriculture Sample Survey is conducted by the National Bureau of Statistics (NBS) and the Office of Chief Government Statistician (OCGS) in collaboration with the Ministries responsible for Agricultural activities for both Mainland and Tanzania Zanzibar. At the National level, the implementation of the survey is headed by the National Bureau of Statistics.
The National Team had the responsibility of overseeing the operational aspects of the survey and the team was comprised of staff from the Department of Agriculture Statistics, in the NBS, staff from the Department of Agricultural Statistics, in the OCGS and representatives the Ministries responsible for Agricultural activities for both Mainland and Tanzania Zanzibar. At the regional level, the implementations of the survey activities were supervised by the Regional Statistical Officers of NBS, OCGS, and the Regional Agricultural Statistics Supervisors from the Ministry of Agriculture, Livestock and Fisheries.
The field organization structure of this Survey consists of a Mobile Response Team, supervisors and enumerators. The Mobile Response Team is responsible for providing overall direction to the field operations and to respond to queries arising outside the scope of the training exercise. Supervisors are the members of the National Team and other staff from NBS-Department of Agriculture Statistics. Their responsibilities are; to supervise the enumerators during data collection activities, to communicate with the mobile team on the queries arising in the field which were outside the scope of the training and to communicate back to all enumerators on the decisions made.
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Tabulation Plan The Tabulation Plan is developed based on the user’s workshop. The developed tables reflect the information needs of end users. It took into consideration the tabulations from previous agriculture sample censuses and surveys to allow trend analysis and comparisons.
Sample Design The area frame approach in conducting AASS is a new methodology to be used in Tanzania. Sample points are selected from the pool of points. For the selected sample points, farm operators are interviewed to provide estimates of crop areas, yields and potential inventories of livestock based on probability of sampled points falling on their respective farm. Land is classified by category and intensity of agriculture called strata into homogeneous blocks. Satellite imagery/area photo of high resolution are analysed and homogeneous blocks are drawn off in GIS. The completed blocks together form an Area Sampling Frame, the process of stratification is the delineation of land into homogeneous areas that share the same amount of agricultural intensity. The purpose of stratification is to reduce sampling variability in the survey results to maintain the uniformity in the population of interest.
Questionnaire Design and Other Survey Instruments The questionnaires are designed following user meetings to ensure that the questions that will be asked were in line with user data needs. Several features are incorporated into the design of questionnaire to increase the accuracy of the data. Variables are coded to reduce post enumeration coding errors. The definitions for each section are included in the enumerators manual so that the enumerator could easily refer to the instructions while interviewing the respondent. Skip patterns are used to reduce unnecessary and incorrect coding of sections which do not apply to the respondent. Both Enumerator and Supervisor Instructions Manuals are used as reference material for supervisors and enumerators.
Pre-testing of the Survey Instruments The pre-testing of questionnaire is done to test the wording, flow and relevance of the questions. Several points are created in different areas in order for the enumerators to locate the points (farms) and the farming operators at those points for interview.
Field Supervision and Consistency Checks Supervision focuses on the completeness of the questionnaires and data consistency. Necessary
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call backs to the respective respondents are made by the enumerators to obtain the correct information. The supervisors adhere to guidelines for control checks.
Data Processing and Analysis Data processing involves the following activities: manual editing, data entry, data structure formatting, batch validation and tabulation.
(i) Manual Editing Prior to data entry, all questionnaires undergo a manual cleaning exercise. This involves checking if the questionnaire has a full set of pages, correct identification and completeness; (ii) Data Entry Normally CSPro software is used for data entry. A team of well-trained data entrants is involved in this process under a close supervision; and
(iii) Batch Validation A batch validation program was developed in CSPro in order to identify inconsistencies within a questionnaire. The procedures varied from simple range checking within each variable to more complexes checking between variables.
Data Quality Control A great deal of emphasis is always placed on data quality throughout the whole exercise from planning, questionnaire design, training, supervision, data entry, validation and cleaning/editing.
Report Preparation Report writing focuses on all activities undertaken during the survey planning, implementation and processing of the field results.
5.13 ANNUAL GROSS DOMESTIC PRODUCT Gross Domestic Product (GDP) is the sum of values added of all domestic producers in the economy. It represents the money value of all goods and services produced within a country out of economic activity during a specified period usually a year, before the provision of the consumption of fixed capital.
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The basic formula for calculating the GDP is:
Y= C+ I + E + G
Where
Y = GDP
C = Consumer Spending
I = Investment made by Industry
E = Excess of Export over Imports (X – M)
G = Government Spending
5.13.1 Objectives of the Gross Domestic Products; (i) To measure the performance of each economic activity in the country. (ii) To measure the contribution of each economic activity in the economy. (iii) To compare economic performance among different economic territories.
5.13.2 Methodology of data production Annual Gross Domestic Product of Tanzania is mainly compiled using production and expenditure approaches.
(i)
Production Approach
In this approach, GDP estimates at market prices are derived by summing up the gross value
added at basic prices of each industry and adding taxes less subsidies on products. This approach
is used for the compilation of all sectors except the government and the Central Bank whose
output is measured at cost.
(ii)
Expenditure Approach
Expenditure approach considers the income expenditure for the purpose of consumption or capital
formation. Not all products purchased by domestic buyer come from domestic production; some
come from outside the country. Therefore, the GDP at market prices by this approach is derived
by adding up the purchases that are made for final consumption, capital formation, and imports
less export (net export).
5.13.3 Reference to applicable Standard Classifications Annual Gross Domestic Product uses the International Standards of Industrial Classification (ISIC Revision 4)
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5.14 QUARTERLY GROSS DOMESTIC PRODUCTS Quarterly National Accounts (QNA) provides up-to-date information for monitoring economic cycles and short-term changes in the economy. It is also a requirement for Tanzania to graduate from GDDS to SDDS.
5.14.1 Objectives of Quarterly Gross Domestic Product
(i)
The main purpose of QGDP is to provide a picture of current economic
development which is more timely than that provided by Annual National Accounts
(ANA), and is more comprehensive and coherent than that provided by individual
short-term indicators.
(ii)
Therefore, QGDP should be timely, coherent, accurate, comprehensive, and
reasonably detailed
5.14.2 Methodology of data production The compilation procedures adopt the same principles, definitions, and structure as the Annual Gross Domestic product (GDP). Currently in Tanzania, only the production approach is compiled in the quarterly estimations. However, compilation of GDP by expenditure approach is still in the work-in-progress stage.
5.14.3 Reference to applicable Standard Classifications Quarterly Gross Domestic Product uses the International Standard Industrial Classification (ISIC Revision 4)
5.15 REGIONAL GROSS DOMESTIC PRODUCT/REGIONAL GDP Refers to coherent, consistent and integrated sets of macroeconomic accounts and tables designed for a variety of analytical and policy purposes but compiled at regional level. In Tanzania Mainland, there are 26 regions and each region constitutes an economic territory used for the compilation of Regional National Accounts.
5.15.1 Objectives of regional gross domestic product (i) To measure the performance of each economic activity in the region.
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(ii) To measure the contribution of each economic activity in the economy. (iii) To compare economic performance among different regions in the country.
5.15.2 Methodology of data production Regional National Accounts are compiled in accordance with International Standards (United National System of National Accounts (SNA). The following two approaches have been recommended for National Accounts Statistics.
(i)
Production Approach
In this approach, GDP estimates at market prices are derived by summing up the gross value
added at basic prices of each industry and adding taxes less subsidies on products. This approach
is used for the compilation of all sectors except the government and the Central Bank whose
output is estimated at cost.
(ii)
Expenditure Approach
Expenditure approach; considers the income expenditure for the purpose of consumption or
capital formation. Not all products purchased by domestic buyer come from domestic production;
some come from outside the country. Therefore, the GDP at market prices by this approach is
derived by adding up the purchases that are made for final consumption, capital formation, and
imports less export (net export).
5.15.3 Reference to applicable Standard Classifications Regional National Accounts are compiled in accordance with International Standards (United National System of National Accounts (SNA). 5.16 NATIONAL ACCOUNTS PUBLICATION The publication of National Accounts of Tanzania Mainland 2007 - 2015 is the first in the series of publications with GDP at constant 2007 prices which provides an overview of the Tanzania Mainland economy. It contains time series of main aggregates such as economic growth, disposable income, final consumption expenditures, imports and exports and regional GDP estimates at current and constant prices for the period of 2007 to 2015.
The main data sources used in the compilation of the National Accounts estimates include, Household Budget Survey (HBS); Agriculture Sample Census; Integrated Labour
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Force Survey (ILFS); Non-Profit Institutions Serving Household Survey; Annual Survey of Industrial Production; Foreign Direct Investment Survey and the Population and Housing Census. Secondary information was extracted from administrative records, which include information on import and export of goods and services, Government Finance Statistics (GFS) and Value Added Tax (VAT) collections. Data from specific studies such as Trade and Transport Margins were also used.
5.16.1 Objectives and uses of the National Accounts Statistics The National Accounts of Tanzania Mainland publication gives consolidated estimates of Gross Domestic Product (GDP) and other allied aggregates of Tanzania Mainland. GDP figures are also available in the “Economic Survey” published by the Ministry of Finance.
The adoption of the United Nations System of National Accounts - SNA 1993 and partly SNA 2008 makes it possible to compare the Tanzania national accounts aggregates with those of other Countries. The concepts and definitions conform to the United Nations recommendations on the subject as given in the United Nations System of National Accounts (SNA 1993).
5.16.2 Methodology of data production The methodologies used are based on the SNA. The following two approaches are recommended for National Accounts Statistics.
(i)
Production Approach
In this approach, GDP estimates at market prices are derived by summing up the gross value
added at basic prices of each industry and adding taxes less subsidies on products. This approach
is used for the compilation of all sectors except the government and the Central Bank whose
output is estimated at cost.
(ii)
Expenditure Approach
Expenditure approach; considers the income expenditure for the purpose of consumption or
capital formation. Not all products purchased by domestic buyer come from domestic production;
some come from outside the country. Therefore, the GDP at market prices by this approach is
derived by adding up the purchases that are made for final consumption, capital formation, and
imports less export (net export).