Classification: Nomenclature statistique des activités économiques dans la Communauté européenne, (NACE Rev. 1.1) (Statistical Classification of Economic Activities in the European Community).
Scope of the data
- Sector coverage: NACE Rev. 1.1, sections A and C to E (agriculture, forestry, industrial products, electricity and gas). For the time being, services coverage includes freight transport as well as architectural and engineering activities.
- Product coverage: 17 main groups with about 820 items.
- Geographical coverage: All of Switzerland.
Types of prices: transaction prices ex-factory gate, VAT and rebates deducted, excise duties included.
In product groups where the prices fluctuate at short notice the data collection is done once a month during the first 8 days of the month. Other prices are collected on a quarterly or half-yearly basis.
Source data collection programs
- Sources of weights: Gross production value or turnover, if gross production value is not available.
- Period of current index weights: Calendar year 2015.
- Frequency of weight updates: The weights are revised and the index re-based every 5 years (2015, 2020 etc).
- Establishment selection: The selection of reporting units is purposive. For each family of products, the sample includes most of the main producers and a sufficient number of small and medium producers.
- Product/Transaction specification: Products with the largest production value based on the national product classification are selected with transaction specifications obtained from producers.
- Sample size: Approximately 10,000 prices are collected from about 1,500 reporting units.
- Price collection methods: Price collection is done in most cases by means of postal questionnaires (shuttle-lists) reported by individual establishments and returned to the FSO as pre-arranged.
Source data statistical techniques
- Treatment of missing prices and selection of replacement items: When a product is temporarily unavailable, the last price collected is carried forward; when a product becomes permanently unavailable, a product with similar quality characteristics and sales conditions is selected as a replacement.
- Adjustments of quality differences: Small quality changes are not taken into account, while prices are adjusted for substantial quality change, wherever quality difference can be quantified; otherwise products are considered as totally new and linked into the index.
- Introducing new products: Reporting units select products with significant market share and where possible with the same quality; quality defined in terms of characteristics listed in product description; list of products reviewed continuously and rules established to introduce new products.
- Seasonal items: Prices are collected for pre-specified months and last available price carried forward for months with no collection; weights held constant throughout the year.
- Verification procedures: The FSO staff asks the reporting units to provide reasons for large variations; automatic validation at FSO; invalidated prices checked by staff. Compilers and statisticians analyze item indices to ensure that changes are consistent with information about product markets.
- Seasonally adjusted indices: No seasonally adjusted indices are published.
- Plans for improvements: Step by step, different services will be integrated into the index.
Other statistical procedures
- Computation of lowest level indices: Unweighted arithmetic average of price relatives for the current and the base period.
- Aggregation formula: Direct Laspeyres with fixed weights.
- Aggregation structure: The products’ basic price indices are aggregated by product groups and sector, by main agricultural and industrial groupings (products of agriculture and forestry, intermediate goods, capital goods, consumer durables, consumer non-durables, energy), by product destination (domestic or export market), and for calculating the core inflation.
- Alignment of value weights and base period: No alignment is made.
- Reference period: May 2015= 100.