The Boston tea party. For sure
Answer:
In the 1920s people were more optimistic about the future because the economy was growing very fast, many people were enjoying new amenities like a vaccuum cleaner or going to the cinema for the first time, and credit was cheap, including mortgages. Nowadays, people are more pesimistic due to recent economic crisis, stagnation of income for many people, and rising inequality.
In the 1920s, people were also much more socially conservative, to the point that during most of the decade, the sale of alcohol was prohibitied. Nowadays, most people are less conservative and more liberal compared with the 1920s past, being more empathetic towards alternative lifestyles, and diverging opinions.
The signal would be: prices.
When the prices of a certain product is high, it would give signals to the seller to increase the production of that product.
the prices also determine how much material and type of production technique that the sellers can afford to use.
