Python lists have limitations when analyzing large data sets. These can be overcome by first converting lists to Numeric python or numpy arrays. Numpy short for N$-$dimensional Array Object is a part of the python scientific package. It provides support for scalar, vector and general data analysis operations on top of list operations. We will use numpy arrays for cyber risk assessment and determining threat likelihoods, severities and risk factors for our organization to identify the most urgent threats. Furthermore we will conduct a cost$/$benefit analysis of the NIST IT controls dataset $800-53$ to deploy controls with the best return on investment.