Distribution of residence duration in owner occupied housing.

Residence duration was determined in owner occupied household by employing tax records that identify changes in ownership. Residence duration was estimated by selecting a random sample of households from Multnomah County, Oregon and using the interval between the two most recent changes in ownership. Residence duration was observed to be consistent with an exponential distribution with a mean of 13.6 years. While mean residence duration in this study was consistent with the results of other studies, the distribution of residence duration in this study was not consistent with the results of another study. The distribution of residence duration is important in establishing the distribution of exposure in a population using probabilistic risk assessment methods.