B. Estimating the Size of the IT Workforce

Estimates of the IT workforce depend, first, on the definition of “IT worker” used. For example, estimating the number of Category 1 IT workers would yield a very different result (Table B.1) than would estimating the combined total of Category 1 and Category 2 workers (Table B.2). Similarly, estimating the number of individuals in software occupations would be a different exercise from estimating the number of individuals in both software and hardware occupations. Second, estimates depend on the data set used in the analysis and on the occupational categories in that data set used as a proxy IT workers as defined by the analysts. Finally, estimates depend on whether the analyst focuses on the number of individuals employed, the number of individuals in the labor force (employed plus unemployed who are seeking), or the number of positions a firm has (filled or vacant).