This guide explains

When opening the spreadsheet, Excel will warn you than

- The average call duration noted
*t*is known.*t*is located on**B7**. - The number of agents, noted
*m*is known.*m*is located on**B8**. - The call arrival rate, noted λ is known. The arrival rate is the number of incoming calls per second. In the spreadsheet, λ is located on
**B9**.

In the following, based on those 3 variables, plus a couple of statistical assumptions, we will be able to compute

- the average agent occupancy.
- the probability that a call has to wait.
- the probability that a call waits for more than a specified time.

The most important statistical assumption is that the incoming calls behave statistically like a Poisson process. Without entering too much into the details, this assumption is reasonable if the call events are

The

The

The

The

`ErlangC`

macro function implemented in Visual Basic. The `ErlangC`

function takes two arguments, first The

`ASA`

macro function implemented in Visual Basic. The `ASA`

function takes 3 arguments, first The

`ErlangCsrv`

which takes 4 arguments: first In this section we propose to use a much more compact layout illustrated in the screenshot below.

Within the sample spreadsheet, the upper-left corner of illustration here above is the cell

A couple of remarks

- we assume constant average call duration
*t*and constant target time*tt*. - we use static Excel cell reference, i.e.
**$A$1**instead of**A1**for the variables (which facilitate cut-and-pasting the formulas). - agent counts can be freely optimized to adjust the expected service levels.
- cell format properties are adjusted to avoid displaying to many decimals.

- ABC analysis
- Business Drivers
- Container shipments
- Economic order quantity
- Fill Rate
- Financial impact of accuracy
- Inventory accuracy
- Inventory control
- Inventory costs (carrying costs)
- Inventory turnover
- Lead time
- Lead demand
- Min/Max Planning
- Multichannel Order Management
- Optimal service level formula
- Perpetual Inventory
- Phantom Inventory
- Prioritized Ordering
- Product life-cycle
- Reorder point
- Replenishment
- Safety stock
- Service level
- Stock-keeping unit (SKU)

- Backtesting
- Forecasting accuracy
- Forecasting methods
- Obfuscation
- Overfitting
- Pinball loss function
- Probabilistic forecasting
- Quantile regression
- Seasonality
- Time-series

- Bundle Pricing
- Competitive Pricing
- Cost-Plus Pricing
- Decoy Pricing
- Long-term maintenance agreement pricing
- Long-term pricing strategies
- Odd Pricing
- Penetration Pricing
- Price Elasticity of Demand
- Price Skimming
- Repricing software (Repricer)
- Styling Prices for Retail