Question

The start of the great depression is usullly pegged to the stock market crash of black tuesday on october 29, 1929 when the dow jones industrial average fell almost 23 percent and the market lost between 8 billion and 9 billion in value which is likely a reason this information is from a secondary source

Answer 1

The information is found in textbooks or in news articles written by reporters, not from someone who was there and witnessed the actual event and recorded it in something such as a diary