1. A computer implemented method of analysing a set of data records, wherein each data record comprises a value for each of a plurality of variables, the method comprising: using one or more computer processors: receiving a selection of a variable of interest from the plurality of variables; analysing values in the data records of at least one variable of the plurality of variables other than the variable of interest by determining whether the at least one variable is correlated with the variable of interest and for each variable determined to be correlated with the variable of interest, determining the strength of the correlation; using the analysis to create a statistical description of said at least one variable; for one or more rules corresponding to the at least one variable, applying the rule to the plurality of variables; for each rule having conditions of the rule met by the plurality of variables, choosing a template corresponding to the rule; using the statistical description to populate the one or more templates corresponding to a rule, the templates populated for one or more variables other than the variable of interest, each template including a natural language description of a relationship between the variable of interest, or a value or range of values of the variable of interest, and the variable to which the statistical description applies; and displaying the one or more populated templates including natural language descriptions for one or more of the variables, together with information relating to the strength of the correlation.