© Copyright INFORM GmbH Estimation Procedure INFORM GmbH, Aachen

© Copyright INFORM GmbH Enterprise Resource Planning (e.g. SAP, Navision,...) INVENT ERP Book Data URDAT Items to be recorded STICHPROBEN Storage Location Structure Analysis Planning Inventory Records Inventory Execution Preliminary Extrapolation Final Extrapolation Results of Inventory STIDAT Current Book Data URDAT Additional Samples STICHPROBEN ERP Inventory Data ERP Book Data

© Copyright INFORM GmbH Interfaces:  Book data in form of the file URDAT  Items to be recorded in the form of the file STICHPROBEN  Parameters Task: Determination of Sample Size Planning

© Copyright INFORM GmbH Full Census Layer: 50 % of the total stock value must be covered (approximately 5-10 % of all items). These items are defined by the complete census limits: Value limit45 % Price limit5 % Results of the Stock location structure analysis Planning

© Copyright INFORM GmbH Sample Range: The remaining items belong to the sample range of which samples are randomly selected. 1 layer:variance of the book data from the smallest book value to the complete census limit  big sample size Sample Space Complete Census Layer 1 layer Ø-value Planning

© Copyright INFORM GmbH Sample Range: The remaining items belong to the.sample range of which samples are randomly selected: 1. Schicht Sample Space Complete Census Layer Schicht 1 layer:variance of the book data from the smallest book value to the complete census limit  big sample size 2 layers:variance reduction in any layer, from the smallest value to the layer limit respectively from the layer limit to the complete census limit  smaller sample size Ø 1 -valueØ 2 -value Planning

© Copyright INFORM GmbH layer:variance of the book data from the smallest book value to the complete census limit  big sample size Sample Range: The remaining items belong to the sample range of which samples are randomly selected: 2 layers:variance reduction in any layer, from the smallest value to the layer limit respectively from the layer limit to the complete census limit  smaller sample size n layers:according to statistics one randomly selected item per layer sufficient  smallest calculated sample size S1 Sample Space Complete census layer S2S3... Sn Planning

© Copyright INFORM GmbH Actual layering:smallest necessary sample size, the actual sample size is the maximum of calculated and minimum sample Sample range: The remaining items belong to the sample range of which samples are randomly selected: S1 Sample space Complete census layer S2S3... Sn n layers:according to statistics one randomly selected item per layer sufficient  smallest calculated sample size Planning

© Copyright INFORM GmbH Stratification:  size / value  ø – value / variance of the book data  the bigger the variance, the bigger the calculated sample size  calculated samples / minimum samples  Actual sample Max [calc. sample/ min. sample] Sample range: The remaining items belong to the sample range of which samples are randomly selected. Random drawing of samples (approx. 200 – 300 samples) Printing of the items to be recorded / file containing items to be recorded Planning

© Copyright INFORM GmbH %Complete census layer - defined by limits Separation into: Preparation of all drawings to be recorded within a file and a list Sample range - division into layers - random drawing Planning (Overview) Planning

© Copyright INFORM GmbH  Generation / Printing of inventory records  Count  Entry of the count  Checking of inventory differences, if necessary correction  Booking of the differences, adjusting of the differences, adjusting the inventory account  Transfer of the inventory results to INVENT when all samples have been counted  Marking / Generation of an inventory records from the interface file Manual inventory in ERP

© Copyright INFORM GmbH Interfaces:  Book data in form of the file URDAT  Items to be recorded in the form of the file STIDAT  Parameters  Additional items to be recorded in the form of the file STICHPROBEN Task: Re-calculation of the sample size on the basis of the available inventory differences and the preliminary results Preliminary Extrapolation

© Copyright INFORM GmbH  Statistics according to layer - Changings / Confirmations - Summation of inventory differences  Error and changing journals - missing confirmations - new items - deleted items - shifted items - items with negative book value  Differences journal - according to quantity and value Journals:  Transfer journal - actual stock and estimated balance at inventory time Preliminary Extrapolation

© Copyright INFORM GmbH  Maximum relative error  Extrapolated accounting difference Preliminary Extrapolation

© Copyright INFORM GmbH Examples for the calculation of value based differences / statistical error: Assumption:1000 items, 30 samples Two extreme cases may occur: I. Case30 samples+ 10,- € Ø difference+ 10,- € extrapolated difference ,- € imprecision (stat. error)< (0) II. Case15 samples+ 10,- € 15 samples- 10,- € Ø difference0,- € extrapolated difference0,- € imprecision (stat. error) > < +/-2% < 1% > 1 %  drawing of further samples < +/-2% < 1% Preliminary Extrapolation

© Copyright INFORM GmbH  Extrapolated accounting difference < +/-2% in total stock  Maximum relative error < 1% in total stock  Statistical error > 1% - Additional samples - new file / printing, continue with „Manual inventory"  Complete confirmations - Additional sample =0, continue with „Final Extrapolation"  Missing confirmations - continue with „Manual inventory" Re-calculation of sample size: Preliminary Extrapolation

© Copyright INFORM GmbH Interfaces:  Current book data in the form of the file URDAT (in case the final extrapolation is nit executed immediately ahead preliminary extrapolation)  Inventory results in the form of the file STIDAT (in case new inventory results are available)  Parameters Task: final result Final Extrapolation

© Copyright INFORM GmbH  Statistics according to layer: - Changings / Confirmations - Summation of inventory differences  Error and changing journals - missing confirmations - new items - deleted items oder  Differences journal - according to quantity and value Journals:  Transfer journal - actual stock and estimated balance at inventory time (in case further results are transferred) Final extrapolation

© Copyright INFORM GmbH  Maximum relative error  Extrapolated accounting difference Final Extrapolation

© Copyright INFORM GmbH Thank you for your attention!