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Lifespan is an essential parameter for the accounting and analysis of material stocks and flows, one of the main research topics in industrial ecology. Lifespan is also important as a parameter that portrays the current and historical situation of industrial metabolism, which is an area of interest to industrial ecologists. In the present article, the available information from various reports on product lifespan was reviewed. Although we found a large number of data for many durables, the definition of lifespan in published articles varied, which limited our ability to compare reported values. We therefore first defined lifespan and then compared the international and historical data. We compiled more than 1,300 data sets from various sources and identified some differences among the types of goods and among regions. With the reviewed data noted in this article, we established a database, named LiVES (Lifespan Database for Vehicles, Equipment, and Structures), and will disclose it on the Internet to share the information. [ABSTRACT FROM AUTHOR]

Lifespan of commodities is essential information for material flow analysis and material stock accounting. Lifespan data is available in the literature; however, it varies in definition and in methodology employed. This article reviews and categorizes different types of lifespan distribution and distribution estimation methodologies, and investigates the relationship and differences between lifespan definitions and estimation methodologies. Lifespan distribution of commodities can be classified into five types from two perspectives: base year for which the distribution is drawn, and vertical axis of the distribution. The methodologies for estimating lifespan distribution were classified into four types and the details of each methodology and the relationship to the definition of lifespan were also clarified. This article also examines differences in actual lifespan data—between the types of distribution, the definitions, and the employed methodologies—by comparing reported data in literature. Any of the four methodologies are theoretically applicable and provide the same value of a lifespan; however unless accurate data such as census statistics are available, lifespan data can vary, and therefore we must be very cautious about the representativeness of sample data. [ABSTRACT FROM AUTHOR]