specifies a triangular distribution with three points — one at the most likely value and two at the specified bottom and top percentiles. The bottom percentile and top percentile are values between 0 and 100. Each percentile value gives the percentage of the total area under the triangle that falls to the left of the entered point. Use of the Trigen function avoids the problem of the minimum and maximum values not actually being possible occurrences in the standard Triang function. This is because in the Triang function these are the points where the distribution intersects the X-axis, or points of zero probability.