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Administrative data are collected depending on requirements and need of producers and users of particular administrative data and not specifically for national account statistics.
• The data collection program provides adequate coverage of economic activities
All economic activities according to ISIC Rev. 4 are covered
3.1.3 Source data are timely.
• The data collection programs provide for the timely receipt of data.
Timeliness of the dissemination of data is met as per release calendar. Release calendar informs on deadlines set for reporting in advance though sometime there is delay of data submission from data source agents.
3.2 Assessment of source data
3.2.1 Source data including censuses, sample surveys, and administrative records are routinely assessed, e.g., for coverage, sample error, response error, and non-sampling error; the results of the assessments are monitored and made available to guide statistical processes.
• Accuracy of the data from surveys is routinely assessed.
The monitoring is done by the respective department responsible for conducting surveys. Information of non-sampling error is available on NBS/OCGS website. This is done during benchmarking and revision of national accounts stastistics process in consultation with respective data producers
The stakeholders workshop/meeting conducted to verify the data collected from the survey/census and the questions required to meet the required objective ie indicators and to verify the consistency with other related source data.
• Accuracy of the information from administrative data and other supplementary sources is routinely assessed.
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Data used to compile national accounts statistics are assessed on quarterly basis.
3.3 Statistical techniques
3.3.1 Data compilation employs sound statistical techniques to deal with data sources
• Data compilation procedures are sound . Compilation procedures are adhered to the international guidelines whereas administrative data are analysed and any errors detected are corrected by contacting the enterprises or government agencies concerned. The current data is also compared with previous years’ data for any given financial and non-financial corporations. Any inconsistencies detected are corrected in collaboration with the reporting institutions.
The accuracy of fiscal data is also assessed regularly, and respondents are asked for clarifications if there are questions. Adjustments are made when necessary and procedures for imputation and adjustment for non- response follow international guidelines.
• Appropriate measures are taken to validate the source data.
Data for missing observations are adjusted by using estimation techniques and the adjustments for under coverage follow appropriate guidelines in line with the international guideline.
3.3.2 Other statistical procedures (e.g., data adjustments and transformations, and statistical analysis) employ sound statistical techniques.
• Sound adjustments are employed to make source data consistent with national accounts requirements.
The assessment of GDP, both in value and volume terms, is based on statistical techniques that are unsound owing to the deficiencies observed in the source data. Informal sector is estimated, however illegal activities are hard to cover, hence difficult to estimate.
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• Output estimates are compiled at a sufficient level of industrial detail.
For production approach, ratios are sometime derived from outdated surveys and censuses and in some industries, data may not be available at the detailed level for national accounts purposes. Likewise, certain techniques are not consistent with the 2008 SNA and ISIC Rev. 4 is used.
• Intermediate consumption estimates are compiled at a sufficient level of detail. Intermediate consumption (IC) is available by industry but details of IC is available for the benchmark year
• The reliance on fixed ratios derived from benchmarks or other sources is monitored.
Fixed ratios have been used over 5 years for some economic activities
• Proper techniques are used to address specific issues of GDP compilation.
Housing production on own account (owner-occupied housing), called imputed rent, is estimated on the basis of the data derived from the Household Budget Survey, which give the costs of different categories of housing. However, the consumer price index line item for housing is used to estimate the imputed rents, with all the shortcomings which that implies.
The estimate is from the HBS & NPS. FISIM is allocated as per 2008 SNA recommendations. Agriculture and construction economic activities estimated using work in progress approach. Inventories are estimated based on the stock of Assets Recording of General government data is partially accrual.
• Proper procedures are followed for compiling volume measures of GDP.
Appropriate Price indices are used to deflate output and intermediate inputs as per 2008 SNA. With exception of few industries.
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• The GDP estimates by expenditure components are derived independently.
GDP by expenditures approach is compiled annually but not independent.
• Expenditure estimates are compiled using detailed
classifications.
Detailed classification indicated in the benchmark year. Annual
movements obtained by extrapolation of benchmark estimates using
appropriate indicators. Final consumption expenditure is estimated for
Household, Government and Nonprofit Institutions Serving Households
(NPISH)
For the household final consumption expenditure, estimates based on
the data from household budget survey conducted in year 2017/18. The
sampling frame base is from the 2012 census.
The household final consumption expenditure estimated by products
plus adjustment for direct purchases abroad by resident less purchases
of non- resident in the territory
Government final consumption expenditure is computed as gross value of output less marketed value of goods and services. The government output is mostly non-market, estimated as sum of compensation of employees, consumption of fixed capital and intermediate consumption.
Gross fixed capital formation (GFCF) compiled based on central government statistics. The estimated GFCF includes investment in building and structure, transport equipment, machinery and equipment, other machinery and equipment, animal resources yielding repeated products and intellectual property. The estimated GFCF include domestic produced goods and imported. Changes in inventories for the benchmark year is estimated using commodity flow approach
Exports and imports of goods and services data obtained for the central bank and extrapolated using appropriate export and import price indices.
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• The reliance on fixed ratios derived from benchmarks or other sources is monitored.
With excerption of few industries, double deflation approach is used and the deflators are reviewed during major revisions (every five years)
• Proper techniques are used to address specific issues of GDP compilation.
Some of the expenses are captured by BOT and HBS & NPS have been
used to estimate the above items. Special issues and treatment: include:
Estimation of output of a central bank at cost, allocation of
FISIM to different users including industries, and estimation of Life and
non-life insurance services separately; Inclusion of imputed rent to
owner-occupiers as part of HH final consumption expenditure;
treatment of durable goods purchased by households (eg. motor
vehicles) for Household use as final consumption expenditure.
• Adequate procedures are followed to compile volume measures of the expenditure components of GDP.
Consumer price indices are used for extrapolation of final consumption expenditures by households and government. the civil service wage rate index, is used is used to deflate wages components.
The double deflation method is used when the data are available, as recommended in the 2008 SNA.
• Specific quarterly compilation techniques are in accordance with internationally accepted good practices.
All of the above items are implemented as per 2008 SNA except seasonal adjustment quarterly national accounts estimates which is not applicable for a moment.
3.4 Assessment and validation of intermediate data and statistical outputs
3.4.1 Intermediate results are validated against other information where applicable.
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• Intermediate results are validated against other independent data.
NA account assess the data given from various sources before compilation.
3.4.2 Statistical discrepancies in intermediate data are assessed and investigated
• The discrepancies in intermediate data are routinely investigated and measures taken to remove them.
NA team assess the data collected from various sources before using for NA compilation and hence remove the discrepancies.
GDP estimates are prepared using production and expenditure approaches. However, discrepancy between estimated GDP by production and expenditure is included in the errors and omissions except for the benchmark year. Verification of the consistency of the data is currently determined by the availability of sources.
3.4.3 Statistical discrepancies and other potential indicators of problems in statistical outputs are investigated.
• The statistical discrepancies, if any, between GDP by activity and GDP by expenditure components are investigated.
The supply and use framework is conducted in every 5 years. The framework is used to crosschecking consistency between the approaches.
Discrepancy is shown in GDP expenditure and when the accounts are prepared, the estimates of GDP according to the two approaches and their reconciliation are useful for detecting and correcting discrepancies.
• Other indicators of problems are investigated.
Data are validated against unofficial estimates, this is due to the fact that it differs significantly from the official GDP Estimates, During benchmarking, conducted studies include NPISH, trade margin and services.
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3.5 Revision studies
3.5.1 Studies and analyses of revisions and/or updates are carried out and
used
internally to inform statistical processes (see also 4.3.3).
• Revision studies are undertaken on a regular basis.
Studies for rebasing and revisions are carried out, and provisional, semi- final, and final accounts are produced
national accounts have been revised as per EAC and IMF guidelines
• Measures are undertaken to incorporate the findings from revision and/or update studies in data compilation.
Revision studies are not undertaken on a regular basis. Therefore, measures are not undertaken to incorporate the findings from revision studies in data compilation.
- Serviceability
4.1 Periodicity and timeliness
4.1.1 Periodicity follows dissemination standards • The periodicity of the statistics follows the IMF data dissemination standards (Special Data Dissemination Standard (SDDS) or General Data Dissemination System (GDDS)) The GDP is disseminated quarterly and annually following the IMF data dissemination standards Special Data Dissemination Standard (SDDS) and General Data Dissemination System (GDDS) respectively. The NBS website http://www.nbs.go.tz and press release is used to disseminate the GDP and its allied aggregates.
4.1.2 Timeliness follows dissemination standards
• The timeliness of statistical series follows the IMF data dissemination standards (SDDS or GDDS)
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The accounts are published timely following IMF data dissemination standards. The quarterly GDP estimates are disseminated within three months after the end of reference quarter (SDDS). The annual GDP estimates are disseminated within six months after the end of reference year (GDDS).
4.2 Consistency
4.2.1 Statistics are consistent within the dataset
• Statistical series is internally consistent
The quarterly GDP estimates are consistent and annual estimates. The
concepts, definition, and classification for compiling quarterly GDP
estimates are the same as those used to compile annual estimates.
Annual National Accounts Statistics is published in the “Annual
Economic Survey”, NBS website (http://www.nbs.go.tz) and “Statistical
Abstract” publications. Annual GDP estimates by production are
consistent by activity and expenditure annually.
The GDP estimates at current prices, volume measures, and (implicit) deflators are consistent within the “value = volume × price” framework
4.2.2 Statistics are consistent or reconcilable over a reasonable period of time
• The statistical series is consistent over time
The Tanzania Mainland GDP Series 1966-2022 is publicly available in the NBS website. Public is informed when then there is change in source data, methodology and historical techniques.
4.2.3 Statistics are consistent or reconcilable with those obtained through other data sources and/or statistical framework
• The statistics are consistent or reconcilable with other statistical frameworks.
The national accounts statistics are consistent with balance of payments, government finance statistics and other statistical framework. However, NBS is the only institution responsible for producing national accounts data
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4.3 Revision policy and practice
4.3.1 Revisions and/or updates follow a regular and transparent schedule
• The practice of revisions (e.g., from provisional estimates, for weight updates, for changes in methodology) follows a predictable pattern of which users of statistics are informed.
The revision cycle is made known to the stakeholders like BOT, TRA, MoF and other users through release calendar.
Six rounds of revisions have been done since the first compilation of national accounts statistics in 1954. The first revision of national accounts statistics in Tanzania was done for the year 1966, the second revision was done for the year 1976, the third revision was for the year 1992, the fourth revision was for the year 2001, the fifth revision was for the year 2007 and the sixth revision is for the year 2015. The revision of national accounts statistics of Tanzania Mainland for the year 2015 used the Supply and Use Tables (SUTs).
Adequate information about the revision is included in the statistical
release publication. When the revision is outside the regular cycle
stakeholders are informed. Quarterly GDP estimates are subject to
revisions during annual GDP compilation, The annual estimates are
published in economic survey publications every year.
4.3.2 Preliminary and/or revised/ updated data are clearly identified
• Users are informed about the preliminary nature of the data.
At the time of data dissemination, users are informed on whether the data disseminated is preliminary or revised as indicated in the the revision policy.
4.3.3 Studies and analyses of revisions are made public
• Users are informed of the results and studies of the revisions to the statistics.
Before rebasing users are informed about the purpose, steps to be undertaken during rebasing, studies reports, analyses of revisions or any updates are explained and documented. Rebasing report is disseminated