The objective of the project was to generate historical estimates and projections of employment demand by industry and occupation (industry-occupation matrices) for the state of Pennsylvania and 12 metropolitan labor market areas in the state. The methodology is discussed in two sections. The first section is concerned with the methodology used in arriving at historical estimates and projections of the industry-occupation matrices. The second section presents procedures used in computing annual change factors for each occupation in each area, for the period 1970-80, given the benchmark years data for 1970, 1975, and 1980. A list of 88 industries is appended. (Author/EC)