Prads -

Is it something I have buy? <

It is possible to perform Monte Carlo simulation using only Excel's built-in
features. The uniform density random number generator worksheet function
RAND can be used with various inverse cumulative distribution functions,
e.g., NORMINV, to generate inputs to your worksheet model. The model can be
recalculated and output values can be tabulated using Excel's Data Table
command. The results can be charted using the Histogram tool or an XY
(Scatter) chart for the cumulative frequency distribution.

Add-ins for Excel automate many of these tasks. Visit Google.com, and search
for "Excel Monte Carlo Simulation" (without the quotes). The
industrial-strength add-ins are Crystal Ball (www.decisioneering.com) and
@RISK (www.palisade.com). Many add-in developers offer tryout versions, like
my own RiskSim (www.treeplan.com).

- Mike
www.mikemiddleton.com