The material in this post came from my efforts to learn about when Arlington’s housing was built. The data comes from the town’s 2019 property tax assessments, where I took our nineteen-thousand-and-some-odd homes and apartments and broke them down by housing type and decade built. It’s not exactly a history housing of production, though it is a close approximation. In this analysis, a single-family home built in the 1912 and rebuilt as a two-family in 1976 would show up as two units built in the 1970s. Similarly, a three-family home that was built in the 1924 and later converted to condominiums would show up as three condominiums built in the 1920s.