# Potential Benefit of Carbon Benchmarking: Analysis of Semiconductor Industry in Taiwan
## 3 Empirical Data Sources and Data Processing  
The empirical analysis undertaken here requires data for input and output variables in the production processes of the Taiwanese semiconductor industry. There are two types of output variables to be considered. The first is desirable outputs, i.e., an indicator measuring the value of the products created during the production process that can provide economic benefits for the producer. This study uses the product sales revenue of individual semiconductor manufacturers for this indicator. The second type of output variable is undesirable output, which is defined as the volume of greenhouse gas emissions generated during the production process by the semiconductor industry. Past studies have generally used indicators such as capital stock, labor utilization, and the cost of goods sold for input variables. Based on the available empirical data, this study then used labor factor costs, net capital, and the cost of goods sold as the input variables. As a result of policy planning requirements, the Environmental Protection Administration (EPA) in Taiwan used a survey to collect variable data for firms in five targeted industries (including the semiconductor industry focused on here) in 2010; the data that firms were required to provide included their energy usage data for different years, CO\({}_{2}\) emission volume calculated using the carbon emissions coefficient method, product output (calculated within the production boundary), etc. However, it is readily apparent from the data included in this EPA database that the specifications of the products manufactured by individual semiconductor firms vary significantly. For example, in the case of integrated circuit (IC) wafer products, the database records the output of six-inch, eight-inch, and 12-inch wafers, etc. Some firms may produce only one product type, while others may produce several. Given the difficulty in implementing assessment on the basis of a breakdown of product types, it was decided to sum together the CO\({}_{2}\) emissions totals for different product types to provide a single indicator for undesirable outputs. Obtaining the data required for desirable outputs (i.e., product sales revenue) and for inputs was much more challenging, because there is a lack of existing databases. To overcome this problem, a search of relevant data for stock market and Over-the-Counter (OTC) listed companies available from Taiwan's Market Observation Post System [36] was taken as the starting point; in addition, financial data for individual firms were collected for consecutive years, so as to provide the data needed for the desirable output and input variables. The main problem for firms' financial data is that the data included in the EPA database are structured by factory, not by company; to ensure consistency with the company-based financial data, the data for different factories belonging to the same company were added together. Following this data processing, the empirical data comprised data for nine semiconductor firms, with a total of 81 observations covering the period 2002-2010. To remove the impact of price fluctuations, data expressed in monetary terms were deflated using 2010 as the base year. Three groups were categorized according to the net sales revenue level.