Life Time Estimations of Japanese Buildings and Houses at the Years of 1997 and 2005

In this paper, I report the results of the life time estimations about Japanese buildings and houses. The estimations are based on the data from the ledgers of buildings for fixed property taxes at the years of 1997 and 2005. The average life time of the detached residential houses was 43 years at 1997, and was 52 years at 2005. The average life times of other types of buildings were also estimated, and which were found to becme longer compared to the previous estimations.