A generalized Q function representation for the transient M/M/1 queue variance is developed. The expression is highly accurate and computationally efficient. In addition, an upper bound on the error is easily calculated. For a Q function relative error of 2.10-12 using Parl's method, the relative error of the variance is generally less than 10-9. Average execution time is on the order of 70 ms per point on a VAX 11/ 750, but faster execution times can be obtained by using larger Q function relative errors. 1988 IEEE
