After the 1950s, the city’s population began to decline slowly, as families tended to be replaced by single people and young couples. The 1980s brought a wave of high-technology startups, creating software such as Visicalc and Lotus 1-2-3, and advanced computers, but many of these companies fell into decline with the fall of the minicomputer and DOS-based systems. However, the city continues to be home to many startups as well as a thriving biotech industry. By the end of the 20th century, Cambridge had one of the most expensive housing markets in the Northeastern United States.
While maintaining much diversity in class, race, and age, it became harder and harder for those who grew up in the city to be able to afford to stay. The end of rent control in 1994 prompted many Cambridge renters to move to housing that was more affordable, in Somerville and other communities. In 2005, a reassessment of residential property values resulted in a disproportionate number of houses owned by non-affluent people jumping in value relative to other houses, with hundreds having their property tax increased by over 100%; this forced many homeowners in Cambridge to move elsewhere.
As of 2012, Cambridge’s mix of amenities and proximity to Boston has kept housing prices relatively stable despite the bursting of the United States housing bubble. Cambridge has been a sanctuary city since 1985 and reaffirmed its status as such in 2006.