2018 Volume 14 Issue 1 Pages 70-76
Lifetime of products is one of the key parameters in LCA and MFA. Lifetime of products is generally regarded as the average of a distribution which is observed from lifetimes of a product group. The average may be different among definitions of distributions. In this article, we introduced six different types of the products’ lifetime distributions. Those definitions can be classified by cumulative or probability distribution; base year for which distribution is drawn, such as shipment year or discard year; and a group for denominators to calculate percentages, such as a group of annually discarded products or a group of annually shipped products. On the basis of the classification, advantages of those different distributions were discussed.
