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This paper expands upon our earlier work involving the concept of Computation-at-Risk (CaR). In particular, CaR refers to the risk that certain computations may not get done within a timely manner. In this paper we examine a number of CaR distributions on several large clusters. The important contribution of this paper is that it shows that there exist CaR-reducing strategies and by employing such strategies a facility can significantly reduce the risk of inefficient resource utilization. Grids are shown to be one means for employing a CaR-reducing strategy. For example, we show that a CaR-reducing strategy applied to a common queue can have a dramatic effect on the wait times for jobs on a grid of clusters. In particular, we defined a CaR Sharpe rule that provides a decision rule for determining the best machine in a grid to place a new job.