The importance of consistent and reliable data cannot be over emphasised. The main sources of data relating to Pakistan’s large-scale manufacturing industries have been the periodical censuses of manufacturing industries (CMIs) which collect data on capital stock, value of output, value added, employment, etc. However, these data suffered from two major defects. First as the censuses failed to cover all the industrial establishments, the data suffered from considerable undercoverage. Second the written down values of capital stock as reported in the CMIs do not reflect actual productive capacities. Therefore an attempt was made earlier in [5, 6] to overcome the problems created by these defects.