Firms make their production decisions based on consumers' needs and wants, that is, there is only supply of goods and services because there is a demand for it. In this way, every consumption decision affects the economy, as it affects production. Production demands resources such as capital, labor and raw materials. Therefore, consumer decisions affect the functioning of the economy as a whole.
A consumer is someone who purchased goods or services. So if people stop buying that certain good or service. Then the economy can go down because there won't be as much money coming in as there was. And then if people buy more of a certain good or service then the economy will go up because they'll be receiving more money. I hope this helps.
However, if we had to point to a particular moment, we might point towards 1920, as this was the year in which more Americans were living in cities than in the countryside for the first time. One of the innovations that had the greatest influence on this shift was the introduction of the assembly line.
