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After data have been collected, the first data entry done in the field and run consistency before the team departing from the cluster.
Tracking and Attrition Tracking implies that enumerators visit again all households, following the same schedule of the previous round. The objective is to track all people present in all the previous rounds of the survey. Three scenarios are possible: the person stayed in the same location or the person has moved to a nearby location, or the person has moved to a distant location. Enumerators are able to keep the previous schedules for households that either stayed in the same location or moved to a nearby location. For households that move to a distant location, their contacts that they provided previously or from the information collected to the neighbors are used to trace the household in its new location and interviews are conducted. Although the NPS tracks individuals, it is relatively common in panel surveys to report tracking and attrition rates in terms of households. A household will be considered successfully tracked if across two consecutive rounds at least one person considered a household member in the previous round is considered a household member in the current round too. The most likely reason for household attrition is the inability to find any person of that household rather than the refusal to participate in subsequent rounds of the survey.
Data Processing The first data entry and editing is done in the field, this ensures that all problems that require going back to the field are solved before the questionnaires are sent to the main office where it may take time to rectify the problems. The second data entry and editing is done at the office to ensure good quality of the data, then data cleaning and validation follow by running the consistence checks to detect any inconsistencies and mistakes either committed in the field and were not seen at both stages of editing or committed at the data entry stage, and if any errors found are fixed.
Analysis, Report writing, and Dissemination of Results After all completed questionnaires have been checked, entered, finalized and analysis completed, the final report have to be prepared. The report has to be detailed and prepared by considering the objectives of the NPS.
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The final report is disseminated through NBS website and the hard copies are found at NBS library for public access.
4.13.3 Reference to applicable standard classifications NPS follow the International reference classifications such as the International Standard of Industrial Classification (ISIC) Revision 4, and the Tanzania Standard Classification of Occupations (TASCO).
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5.0
ECONOMIC STATISTICS
5.1
ANNUAL SURVEY OF INDUSTRIAL PRODUCTION (ASIP)
Industrial statistics play a very crucial role in determining the growth of industrial sector and its
contribution to the GDP. Annual surveys of industrial production data are basic industrial statistics
according to UN International Recommendations for Industrial Statistics. Indicators from
industrial statistics are directed towards policy concerns and successful outcomes and conclusions
for policy.
5.1.1 The objective and uses of the ASIP The survey aims at producing basic industrial statistics in accordance with the UN International Recommendations for Industrial Statistics so as to ensure national and international comparability. The survey is designed to:
(i)
Collect statistics on the characteristics and structure of the industrial sector in the
country;
(ii)
Assess the contribution of industrial sector to the overall economy;
(iii)
Obtain data for computing national accounts estimates;
(iv)
Obtain data for the construction of Input-Output tables
(v)
Assess the current status of the industrial sector in the country;
(vi)
Identify challenges that affect firm-level productivity and competitiveness;
(vii)
Secure inputs for reviewing economic policies, programmes and strategies that
support sector-productivity and growth;
(viii) Provide facts to support dialogue with the Government and other development
partners so as to enhance public-private sector partnership; and
(ix)
Update the existing data for Monitoring and Evaluation at the level of industrial
sub-sectors.
5.1.2 Methodology of data production Reference period Data are requested for and in many cases supplied on a calendar year basis. Those units of enquiry that could not supply data according to calendar year due to allocation problems are advised to supply the data according to the financial years that cover larger part of the reference calendar year.
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Unit of enquiry The statistical unit is an establishment, which is defined as an economic unit, under a single ownership or control, engaging one or predominantly one kind of economic activity at a single physical location (i.e. an individual firm, mining, factory or workshop). However, due to record keeping practices, it is not always possible to strictly follow the definition of an establishment as stated above. In some cases, the restrictions especially on location are relaxed.
Scope and coverage
Scope
The survey covers all industrial establishments with ten or more workers as per International
Standard Industrial Classification (ISIC) Revision 4. The industrial sector is comprised of
establishments engaged in, “Mining and quarrying” (ISIC Revision 4, Section B),
“Manufacturing” (Section C), “electricity, gas, steam and air conditioning supply” (Section D) and
“water supply, sewerage, waste management and remediation activities” (Section E).
Coverage Due to budget constraint, the survey covers all industrial establishments with ten or more workers (persons engaged). For small establishments with 1-9 workers are covered during the census of industrial production which is supposed to be carried out after every ten years depending on the availability of financial resources.
The questionnaire The questionnaires conform to the International Recommendations for Industrial Statistics of the United Nations and incorporates the stakeholders’ requirements. The questionnaires are designed to ensure that the information to be collected satisfy the needs of national accounts, the Government, researchers and the business community.
The information collected through the questionnaires includes; general information, employment, labour and production costs, output, value of inventory and value of fixed assets.
Data collection Data collection is undertaken by a trained team of enumerators under the supervision of supervisors from NBS headquarters. Training of field-staff takes place after the Training of
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Trainers (ToT). The NBS is responsible for the training of supervisors. The supervisors are then responsible for the training of enumerators in the regions.
Fieldwork is conducted by total enumeration to the establishments. The field-staff visit all the establishments and assist them in filling-in the questionnaires. Respondents are asked to provide the data from their accounting records for the reference calendar year.
Data processing Completed questionnaires are sent to the NBS headquarters where they are edited and coded by NBS staff. The data entry system used is CSPro after which the data are transferred to Microsoft Access for generation of tables. Estimates are made by means of substitutions using the secondary data of previous ASIP. A cleaned dataset is then used to generate preliminary tables as per approved tabulation plan.
Organisation of the Report The report presents the industrial statistics according to the latest UN recommendations (2008). The tables are grouped separately at the end of the report and refer to establishments with 10 or more workers.
The report also presents the main results relating to both quantitative and qualitative information that were also collected through the survey. Tables referring to such information are integrated within the section giving the major findings. The tables therefore refer to the respondents only as indicated therein.
5.1.3 Reference to applicable standard classifications Establishments are classified into industries on the basis of major activity in conformity with the International Standard Industrial Classification (ISIC) Revision 4. Each industry is basically defined in terms of its principal products or services, these being similar in nature or commonly associated in production
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5.2 THE INDEX OF INDUSTRIAL PRODUCTION (IIP) Index of Industrial Production describes changes of the volume of goods and services produced over time. Its main purpose is to provide a measure of the short-term changes of value added in volume measures over a given reference period.
5.2.1 Objective and uses of the Product
The survey aims at producing basic quarterly statistics on major commodities according to UN
International Recommendations for Industrial Statistics. The survey is intended to:
(i)
Collect quarterly commodity statistics on the operating characteristics and
structure of industrial sector in the country;
(ii)
To identify the turning points of industrial production at early stage;
(iii)
Assess the contribution of industrial sector to the overall economy;
(iv)
Obtain data for computing National Accounts estimates;
(v)
Assess the current status of the industrial sector in the country;
(vi)
Obtain data for the construction of Input-Output tables;
(vii)
Indices are used in economic policy making and forecasting future economic
performance in the industrial sector;
(viii) Identify conditions that affect firm-level productivity and competitiveness; and
(ix)
Update existing Monitoring and Evaluation data at the level of industrial
establishments.
Uses of IIP The IIP is an important short-term economic indicator in official statistics; the turning points in economic activity can be identified as early as possible and reflects the volume developments in value added over time. Also, IIP is a key input for calculating volume measures as part of the compilation of the quarterly national accounts.
5.2.2 Methodology of Data Production
Scope and Coverage
The Index of Industrial Production (IIP) measures the changes in the quantities (volume of goods
and services) of a constant basket of goods produced by different industrial sectors. The IIP
follows the recommended International Standards Industrial Classification of all economic
activities (ISIC) Revision 4 to enhance international comparability. IIP covers five economic
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zones in Tanzania Mainland and four sub sectors of the economy, namely; mining and quarrying, manufacturing; electricity, gas, steam and air conditioning supply; and water supply (sewerage, waste management and remediation activities).
Data Collection Data for the Quarterly Survey of Industrial Production is collected through questionnaires which are sent the regional statistical offices at the end of the reference period and later distributed to the respective establishments. Questionnaires are collected in the first month after the end of the reference period. Follow-ups are made by physical visits and telephone calls. Where necessary, a team of supervisors is sent to the regions to speed-up the process.
The survey collects quarterly data (for three monthly) on quantities produced with standard units for all major commodities produced by the establishment, together representing at least 70% of value added. Both the establishments and the commodities are classified according to International Standard Industrial Classification of All Economic Activities (ISIC) Revision 4. In addition, the questionnaire asks for the establishment's number of employees, total labour cost and the turnover during the quarter. The accuracy of the responses is verified both at the regional offices and at NBS headquarters.
Data Processing and Analysis Data processing takes place centrally at the main office. The basket weights refer to base weight of value added obtained from the 2008 ASIP for each establishment. Indices are calculated at the item level by comparing the volume of production in the current period with that in reference (base) period. The result at first stage is a set of volume ratios for the elementary items in the index series. The elementary indices are subsequently aggregated as weighted averages to obtain the indices at higher levels. The base weighted Laspeyres index is used for production index series.
Periodicity The IIP is compiled and disseminated on a quarterly basis.
Timeliness The IIP is released six weeks after the reference period
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5.3 CENSUS OF INDUSTRIAL PRODUCTION Census of Industrial Production provides comprehensive information that can be used to assess the impact and outcome of the implemented industrial policies and programmes.
5.3.1 Objectives and uses of the Census The main objective of the Census of Industrial Production is to provide information on economic characteristics of the industrial sector. The information gathered can be used to facilitate the improvement of industrial performance, designing policy, planning, monitoring and evaluation of programmes and providing advice to the sector so as to achieve sustained products quality and productivity.
Specific Objectives aimed at up-dating:
(i)
The structure, composition and activities of the industrial sector in the economy;
(ii)
The contribution of the sector to GDP;
(iii)
The list of commodities to be used in the construction of Indices of Industrial
Production (IIP), Producer Price Index (PPI) and National Accounts;
(iv)
Information for evidence-based formulation of the sector policies;
(v)
Factors influencing the growth and structural changes in the sector;
(vi)
Marketing information; and
(vii)
The list of establishments or a sampling frame for establishment based surveys.
5.3.2 Methodology of Data Production Scope and Coverage The Census of Industrial Production follows the International Standard Industrial Classification (ISIC) Revision 4 to capture all economic activities. The census covers all establishments that engage ten or more persons (referred to as large establishments) disaggregated into 10 to 99 persons (referred to as medium) and those with 100 or more persons (referred to as large), and a sample of establishments which engage less than ten persons (referred to as small establishments). Generally, the census includes establishments engaging in any of the following four industrial sub-sectors; mining and quarrying, manufacturing, electricity, gas, steam and air conditioning supply, and water supply, sewerage, waste management and remediation activities.