American economists describe gentrification as a natural cycle: the well-to-do prefer to live in the newest housing stock. Each decade of a city's growth, a new ring of housing is built. When the housing at the center has reached the end of its useful life and becomes cheap, the well-to-do gentrify the neighborhood. The push outward from the city center continues as the housing in each ring reaches the end of its economic life. They observe that "gentrification" has three interpretations: (a) "great, the value of my house is going up, (b) coffee is more expensive, now that we have a Starbucks, and (c) my neighbors and I can no longer afford to live here ("community displacement")".