Analyzing Planning Levels and Key Figures

Objective

After completing this lesson, you will be able to process key figures and planning levels.

Introduction to Key Figures for Inventory Optimization

Initial premises to understand input and output key figures:

Inventory Optimization

SAP Integrated Business Planning (IBP) for inventory recommends total inventory targets to maximize profit while buffering for uncertainty and maintaining customer service levels. Using SAP IBP for inventory optimization positions stock to absorb uncertainties, such as the following:

  • Forecast error
  • Demand Variability
  • Supply uncertainty

By using a set of stochastic mathematical algorithms, inventory optimization determines the lowest stocking cost possible for locations across an entire supply chain and provides stocking targets directly to planners at an item-location-time period level of granularity.

How Uncertainties Lead to Ineffective Stocking Levels?

Uncertainties multiply across the supply chain due to the interdependency between suppliers, plants, warehouses, and customer sites. If you only consider one portion of a supply chain, you may hold too much safety stock at one location, which leads to increased holding costs, or holding too little safety stock at one location, which leads to stock-outs that either cause lower customer service levels or increased cost due to expedited orders.

The following table lists some common variables which cause uncertainty that lead to ineffective stocking levels:

Customer sideSupply side

Simultaneous internal and external demand varying for stock

Batch size requirements

Errors in demand forecasting

Late shipments

Demand that varies by season or time

Frozen planning windows

Over-forecasting or under-forecasting demand

Multiple supply sources

Outliers and unplanned spikes in demand

Seasonal supply sources

Variability in deliveries to warehouses

Regulatory Quality Assurance production holds

Late changes in promotional event plans, such delayed execution or changes in the planned scope

Forecast error of raw material sourcing

Why Optimizing Safety Stock?

Inventory optimization helps manage uncertainty in the supply chain by determining the amount of safety stock to hold at stocking locations within the supply chain. Safety stock absorbs uncertainty, allowing you to maintain customer service levels. Inventory optimization determines the optimal safety stock for each stocking location and recommends targets, based on the following:

  • Demand from customers and demand uncertainty (direct demand), and the impact that has on internal replenishment orders (indirect demand and indirect demand uncertainty).

  • Forecast error and its impact across the supply chain.

  • Lead times and their variability, replenishment frequency, and lot sizes.

  • Target service levels at customers.

The resulting recommended inventory levels balance risk and cost appropriately. Not every location will see a reduction in inventory, but the entire supply chain will achieve a cost reduction of inventory while maintaining service levels.

Optimal Inventory Placement

Optimal inventory placement is based on inventory forms and purposes, that is, on inventory components. Inventory components comprise the total inventory for a given product.

Calculating inventory components and their targets strengthens inventory optimization. Inventory components include estimates, targets, average quantities, and currency values. An example of inventory components include the following:

  • On-hand stock – inventory that is physically in the supply chain, that is cycle stock and safety stock

  • Cycle stock – inventory that is used to fulfill orders

  • Pipeline stock – stock on order

  • Safety stock – stock kept in reserve to meet unexpected demand and prevent stock-outs

    The following figure illustrates the inventory replenishment process and the components involved:

The figure describes the Inventory Replenishment Process.

In the basic inventory ordering process, there is a periodic review where a planner looks at the current stock and what will be arriving, and compares that to forecast demand, which determines the committed inventory (on hand plus on order). If the committed inventory falls below the calculated target inventory position, you order up to the target inventory level.

Target Inventory Position

The correct target inventory position (TIP) for a location is the amount of inventory needed to:

  • Meet current demand

  • Meet future demand until the next order is received

  • Cover demand uncertainty

TIP is calculated based on forecasts and includes the following types of inventory:

  • Pipeline stock

  • Cycle stock

  • Safety stock

Note

TIP is independent of the committed inventory. For example, in a demand ramp-down situation, there may be enough inventory to cover future demand without placing an order.

The following figure illustrates the components of the target inventory position:

The figure describes the Target Inventory Position.

Now that we have a context, we will address Key Figures within SAP IBP for Inventory remembering that Key Figures reflect all transactional values mentioned before.

Key Figures

Key figures are a series of numbers over time, where each number corresponds to a particular time period value. The following main characteristics are to be highlighted:

  • Key figures have a business context: In SAP Integrated Business Planning (IBP) for Supply Chain, end users view and use key figures in the planning views or in Analytics.
  • Key Figures represent transactional data.
  • Every key figure has a base planning level.
  • Key figures are associated with a key, which is a combination of attributes from one or more master data objects.
  • Key figures represent variables that are associated with attributes (master data types), and can be imported into the SAP IBP system, calculated, and/or manually edited.

Examples of key figures are sales forecast, marketing forecast, consensus demand plan, projected inventory, capacity plans, or actual data such as sales orders and shipment history.

Once you have created your attributes, master data types, time profiles, and planning areas and levels, you define the key figures you want to include in your planning model.

Note

For more information about key figures see SAP Help PortalTypes of Key Figures.

Attribute as Key Figures

An attribute as a key figure is a specially configured master data attribute. It can be used to create planning data such as planning objects or key figure values for specific use cases. The planning data is created when master data is created or updated for the master data type.

The configuration as an attribute as key figure is an optional configuration that can be used for attributes of data type DECIMAL. Depending on how this attribute as key figure is configured, either planning objects only or planning objects and key figure data are created when master data is created or updated for the master data type.

You can use this configuration for attributes that are assigned to a simple, a compound, or an external master data type, that is, to a master data type that you can load data into.

If you define an attribute as key figure in a planning area, the definition for the attribute is specific to that planning area. It does not make an attribute as key figure in other planning areas. This also gives you the option to define an attribute as key figure differently in every planning area.

Irrespective of the kind of planning data you want to create, you need to specify a base planning level. The planning data is then created on that base planning level.

Note

To guarantee that data uploads successfully, use the SAP Key Note 2694269.

To improve the performance using From and To Period functionalities, see SAP Key Note 2550296.

In addition, to delete the values of an attribute as Key Figure without inconveniences, consider SAP Key Note 2370446 too.

Key Figures for Inventory Optimization

Key figures are used by the inventory optimization algorithms and consist of the following:

  • Input key figures

    Either enter values for input key figures during a planning session or upload them from an external system.

  • Intermediate output key figures

    The single-stage optimization algorithm uses intermediate output key figures from the multistage optimization algorithms as input key figures.

  • Helper key figures for input key figures

    These key figures support unit of measure conversion for specific input key figures.

  • Helper key figures for output key figures

    These key figures support unit of measure conversion for specific output key figures.

  • Output key figures

    The inventory optimization algorithms use the input key figure values and intermediate output key figures in their calculations and populate the results into the output key figures. As well as viewing the output key figures, you can copy them into another key figure (for example, using a copy operator).

The type of algorithm determines which input key figures are used. The type of algorithm also determines which key output figures are calculated; some algorithm types only compute values for a subset of output key figures.

We recommend using the names shown on the images. The names are used in the product documentation, but you can change them to suit your own requirements.

Note

To run the inventory operators, you must define the technical IDs of the key figures exactly as shown here (Key Figure ID column). If you change the technical IDs, the operators will fail.

For sample data, planning view templates, predefined dashboards, configuration guides, test scripts, and more pertaining to SAP IBP for inventory, see SAP Best Practices for SAP IBP. You can download the content at http://rapid.sap.com/bp/rds_ibp.

The following figures provide input values for the inventory optimization algorithms, and are delivered with the sample planning areas of SAP IBP.

The figure describes the Input Key Figures.
The figure describes the Helper key Figures Supporting UOM Conversion for Input Key Figures.

Outputs from SAP Integrated Business Planning for Inventory

The figure describes the Output Key Figures.
The figure describes the Output Key Figures.

Here, we explain some examples of output key figures:

  • RECOMMENDEDSAFETYSTOCK: This key figure describes the quantity that should be in stock as safety stock per product and location. In the following figure, on the right, this quantity is the point on the x-axis where the non stock-out probability is reached (either internal or customer facing).The figure describes the Safety Stock Level.
  • The TARGETINVENTORYPOSITION (TIP) is derived from the safety stock level. TIP is considered the upper level of an (s,S) policy. It is the safety stock increased by the expected demand during the exposure period (sum of period between replenishment and lead time).

    (s,S) Policy is a minimum/maximum inventory policy. When the inventory level on-hand falls below a minimum, s, the site will generate a request for a replenishment order that will restore the on-hand inventory to a target, or maximum, number, S. When using this policy, the Reorder Point field is the minimum, or trigger level. The Reorder/Order Up To Qty field is the maximum, or the number to which the inventory level is restored. The behavior of the system depends on how often inventory is checked. So, it is important to select the appropriate Review Period.

  • AVAILABLEINFULL: This key figure contains the probability that the demand can be fulfilled. In the following figure, this probability is equal to the area (integral) up to the safety stock level. In other words, it is the non-stock out probability value on product-location-customer group demand stream calculated from target service level (non-stock out probability or fill rate).

    For customer facing nodes, this is equal to the weighted sum of all service levels requested by the connected demand stream (input).

    For internal nodes, the key figure contains the result of the optimization (output).

    The figure describes the Non Stock-Out Probability.
    This Key Figure is used as an input into the single stage simulation.
  • LOSTCUSTOMERDEMANDMEAN: This key figure contains the probability that the demand cannot be fulfilled, weighted with the quantity. The following figure shows the probability for a stock out on the right side. This area, weighted with the difference between the quantity and the safety stock level, is the expected lost demand mean (fill-rate) or total quantity (non-stock out probability). In other words, it is the expected quantity of demand at customer facing node that cannot be met from planned inventory when demand is greater than what is covered by target service level.The figure describes the Total Probability of Stock-Out.

The following table shows a summary of the relevant main output key figures:

Output: Main Key Figures

Key FigurePlanning LevelsDescription
AVAILABLEINFULLWKPRODLOCCUSTGROUPNon-stockout probability service level
LOSTCUSTOMERDEMANDMEANWKPRODLOCCUSTGROUPAverage expedites
RECOMMENDEDSAFETYSTOCKWKPRODLOCRecommended safety stock
TARGETINVENTORYPOSITIONWKPRODLOCTarget inventory position

Output Key Figures: Network Internal Key Figures

The key figures shown in the following figure contain the internal demand between the different supply chain stages.

In addition to these key figures, there is also information on the standard deviation (suffix STDDEV, instead of MEAN).

The figure describes the Key Figures for Internal Demand.

The dependent demand on an edge (product – location-sourcing from) is calculated using the customer forecast propagated to each stage using the (time-dependent) sourcing ratios and transformations through production (bill of materials) shifted by the lead time (static or stochastic).

The figure describes the Network Internal Key Figures.

The propagated demand is the sum of the demand from all incoming edges. The difference to the key figures described earlier is that this key figure is defined per product-location combination.

The figure describes the Network Internal Key Figures

Key figures show the internal and customer facing service level. Technically, all key figures follow the same logic as previously explained for AVAILABLEINFULL.

The figure describes the Network Internal Key Figures.

Backlog can be found in these key figures with mean and standard deviation (MEAN / STDDEV). Technically, all key figures follow the same logic as previously explained for LOSTCUSTOMERDEMANDMEAN.

The figure describes the Network Internal Key Figures.

Inventory Optimization Planning Levels

A planning level is a set of attributes that identifies and labels key figure values. All inventory key figures are calculated or stored at a specific planning level.

A key figure may exist at many different planning levels and can be queried at these levels, as follows:

  • Base planning level. This is the planning level on which the key figure data is stored.

  • All other planning levels are used for calculations.

The following figures display the planning levels for inventory optimization:

The figure describes the Planning Levels.
The figure describes the Planning Levels.
The figure describes the Planning Levels.
The figure describes the Planning Levels.
The figure describes the Planning Levels.
The figure describes the Planning Levels.