1. 3-4-Dec-07 Meeting of the Working Group “Agricultural Accounts and Prices” 4.3. Prevalidation of APS data (Doc. ASA/AAP/101)

2. 3-4-Dec-07Prevalidation of APS data  In the context of introducing the new web-based data collection and pre-validation system under eDAMIS, the APS data collection should fulfil minimum requirements as regards data quality  The proposed pre-validation rules set out in this document are in line with the new version of the Handbook on Agricultural Price Statistics (Doc. ASA/AAP/100) and the proposal on the treatment of seasonality (Doc. ASA/AAP/099)  The aim of this document is to communicate the most important (minimum) methodological requirements as regards the Agricultural Price Statistics. Introduction

3. 3-4-Dec-07Prevalidation of APS data Minimum methodological requirements General All items in the SDTT should be completed. The exceptions are when the product in question does not exist in the given country (i.e. olives, citrus fruits in Finland etc.) Weighting scheme (API) 1.Vertical aggregation - the sum of product weights is always equal to the weight of the product group. This rule is fully applicable for all products (output and input/seasonal or non-seasonal), both for the annual and for the quarterly data. 2.Horizontal aggregation - the sum of the four quarterly value weights of any single product must be equal to the annual value weight of the same product

4. 3-4-Dec-07Prevalidation of APS data Agricultural Price Indices  The API calculation must be done using the weighting scheme provided to Eurostat for the base year Vertical aggregation: at group level, weighted average using the elementary indices of each product from the group and the value weights of the product from the weighting scheme Horizontal aggregation: weighted average of the elementary indices from each quarter at the product level using the value weights of the product’s quarters from the weighting scheme

5. 3-4-Dec-07Prevalidation of APS data Absolute prices  A comparison between the price levels of consecutive years. For all input and output products the change between consecutive years may not exceed (in percentage) 150% and may not be less than 50% (could be refined in a later stage). This control will detect in particular whether the country uses an incorrect unit of measurement for a certain product (i.e. price per 1000 kg instead of price per 100 kg) and will flag those products for which the price variation is higher or lower than the normal range without any explanation.

6. 3-4-Dec-07Prevalidation of APS data  Member States are invited to comment on the checking rules listed above and to propose additional ones by the end of February 2008. Questions