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We have compiled a list of common questions about CC-Excel.  Please contact us if you have any other questions.

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Index of questions

  1. How do I use the call centre functions in my own workbooks?
  2. Do you include an example workbook?
  3. How are the results reached?
  4. Are the results accurate?
  5. How do I deal with 30 minute analytical intervals?
  6. What service level targets can I specify?
  7. How does CC-Excel differ from Erlang for Excel?
  8. What is included with CC-Excel?
  9. What are the operational limits of the functions?
  10. Can I share workbooks I create with my colleages?
  11. Do you sell the source code, or a DLL to which my own programme can connect?
  12. If I download the software on to my desktop, will I be able to subsequently transfer the software to my laptop?

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Purchasing CC-Excel

How do I use the functions?

Using CC-Excel's functions is no different from using any of Microsoft Excel's built in functions.  You can enter them in your own workbooks, which can be as simple or as complicated as you have the time and imagination to develop!

Excel Functions begin with an equals sign (=) followed by the function's name and its arguments.   Functions perform particular calculations on the arguments, which are enclosed inside round brackets following the function name.  The arguments can be numbers or references to other cells.

With CC-Excel, the functions perform call centre calculations.  For example, a cell with this function:


will display the result 81, which means that 81 agents are estimated to be required to answer 1050 calls per hour of duration 250 seconds, where the average speed of answering the calls is 10 seconds.

Here is a complete list of the functions made available by CC-Excel.

Function name Description
CCXLAgents() Estimates the number of agents required to handle incoming calls within specified service level parameters.
CCXLCalls() Estimates the number of calls that an inbound call centre can handle within specified service level targets.
CCXLDuration() Estimates the average length call that a call centre if the number of agents and number of incoming calls are known.
CCXLASA() Estimates the average speed in which calls will be answered.
CCXLQueue() Estimates the average number of calls that will be queued and waiting for presentation to an agent.
CCXLOccupancy() Estimates the percentage of their time that agents will be busy handling inbound calls.
CCXLAllBusy() Estimates the percentage of calls that will arrive while all agents are occupied and will therefore enter a queue.
CCXLService() Estimates the percentage of calls that will be answered within a specified service time.
CCXLLines() Estimates the number of telephone lines that are required to handle the inbound calls into a centre.

Do you include an example workbook?

An example workbook is installed with CC-Excel and available from the Start Menu.  It has two areas:

The Calculators worksheet shows calculators for each of CC-Excel's functions.  You can use them as a regular tool within the workbook, or treat them as examples of how to create your own tools.

CC-Excel Calculators worksheet

The Ansapoint worksheet demonstrates how you can use the functions to build more complicated tables for estimating many aspects of a call center's operation.  The format emulates Ansapoint, our Windows workforce management product.

CC-Excel Ansapoint worksheet

How are the results reached?

The results produced by CC-Excel are reached using the Erlang traffic models.  These were developed in the first half of the twentieth century to model the performance of telecommunications systems.

Are the results accurate?

Our experience is that the models are accurate, but the Erlang C traffic model makes the following assumptions:

• Calls are offered randomly to a queue (Poisson arrivals).

• Users wait if they find the system busy.

• Service times are exponential.

• Users are served in the order of arrival.

• Users are directed to the first available server (agent).

• Queue sizes are unlimited.

30 minute intervals

CC-Excel's call center functions assume that call volumes are based on the number of call handled during a one hour period.  In some cases, call volumes for only thirty minutes are available. Before these are applied as an argument to a CC-Excel function, these numbers must be doubled to convert them to hourly figures.

For example, consider the following use of the CCXLAgents() function:

=CCXLAgents( B2 , 180 , 80 , 20 )

which would be used to estimate the number of agents required such that 80% of calls were answered within 20 seconds.  The function assumes that the number of calls specified in cell B2 relates to a period of one hour.  If cell B2 contained a thirty minute call volume, then the value should be double, like this:

=CCXLAgents( B2 * 2 , 180 , 80 , 20 )

The CCXLCalls() function returns an estimate of the number of calls that an inbound call centre can handle in one hour.  If a figure for thirty minutes is required, then the function result should be halved.

Similarly, if fifteen minute analytical intervals are to be used, function arguments should be multiplied by four and function results should be divided by four.

What service level targets can I specify?

There are three CC-Excel functions in which a service level target is specified: CCXLAgents(), CCXLCalls() and CCXLDuration(). There are two formats in which you can specify the operating targets for your call centre:
  1. The percentage of calls answered in x seconds
  2. The average speed in which all calls are answered

These three functions support both forms of service level targets. If four arguments are provided with a function, then the first format is assumed. The third argument should be the percentage value and the fourth argument should be the "answered in" value. If the are only three arguments, then the final argument will be the average speed in which calls are answered (ASA).

CC-Excel and Erlang for Excel compared?

We created Erlang for Excel in 1999 and continue to sell updated versions of it today.  Erlang for Excel is an Excel add-in that provides functions for Erlang B, Extended Erlang B and Erlang C.  It includes two call centre functions (ErlCAgents and ErlCalls).  The remaining six functions relate to telecommunications network design.

By contrast, CC-Excel is a specialist product for Call Center management and includes nine functions for calculating many aspects of contact center performance.  We have also introduced two formats for specifying the service level targets for three of the functions (see previous section).

What is included with CC-Excel?

CC-Excel includes:
  • 9 call center staffing functions for Microsoft Excel, packaged as an add-in
  • 12 example calculators provided in an example workbook
  • A staffing table for estimating call centre staffing requirements and performance in an Excel worksheet
  • Full user guide and function reference in PDF and Windows Help formats

What are the operational limits?

The limits for parameter values vary depending on the function being used, but most functions have the limits shown in the table below.   There can also be upper limits on the results.  If a calculation is out of range, then the result cell will show #NUM!

More details information on each function is available in the CC-Excel User Guide.

Operating system All 32 and 64 bit versions of Microsoft Windows.
Excel versions All Excel versions from Excel 2000 (32 and 64 bit versions)
Traffic model used Erlang B and Erlang C
Operational limits Calls per hours Agents Call duration
Up to 300,000 Up to 10,000 Up to 7,200 seconds

Can I share workbooks with my colleagues?

The calculations behind Excel add-ins are not transportable within workbooks. Only a reference to the functions' names are embedded within workbooks and the calculations themselves are resolved using coding that is integrated within an Excel installation. This means that any person wishing to make use of the workbooks you create must also have CC-Excel installed locally on their computer.

Do you sell source code or DLLs?


Will I be able to install on my laptop?

If you purchase the software when you are using your desktop computer, then you may transfer the installation file to your laptop computer and install it there.  However, you may not install on both computers if you are only covered by one single user licence; you will need to buy two licences.

Has this answered your question?

Your question may be answered in the CC-Excel User Guide.  If not, then please send us an email.

Purchasing CC-Excel

The full working version of CC-Excel is available for 99 US Dollars.

Usually, the software can be working on your PC in under 10 minutes!

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Last modified: 14 July 2014

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