The share of American households with guns has declined over the past four decades, a national survey shows, with some of the most surprising drops in the South and the Western mountain states, where guns are deeply embedded in the culture.

The gun ownership rate has fallen across a broad cross section of households since the early 1970s, according to data from the General Social Survey, a public opinion survey conducted every two years that asks a sample of American adults if they have guns at home, among other questions.

The rate has dropped in cities large and small, in suburbs and rural areas and in all regions of the country. It has fallen among households with children, and among those without. It has declined for households that say they are very happy, and for those that say they are not. It is down among churchgoers and those who never sit in pews.

The household gun ownership rate has fallen from an average of 50 percent in the 1970s to 49 percent in the 1980s, 43 percent in the 1990s and 35 percent in the 2000s, according to the survey data, analyzed by The New York Times.