Is getting rarer:
[O]ne trend in the pattern of American social life is curious: Americans have never been less likely to be friends with their neighbours than before. In 1974, 44% of respondents said that they had spent a social evening with neighbours more than once a month. By 2008, that number had dropped to a tick over 30%. Over the course of the study’s existence, the number has been dropping consistently.
The effect is not quite uniform. The likelihood of socialising with neighbours more than once a month declines with age but levels off among the middle-aged before a brief fillip among the elderly. By way of contrast, there have been steady increases in the number of people who socialise with friends (43%) or relatives (60%) more than once a month. Moreover, it is highly dependent on location. People in rural areas are much more likely to spend time with their neighbours than those in urban areas. Residents of suburbs exhibit the lowest level of neighbourliness.