Money The stock market crash of 1929 was 90 years ago. Could it happen again? October 14, 2019October 14, 2019 Russ Wiles, Arizona Republic Comments Off on The stock market crash of 1929 was 90 years ago. Could it happen again? The roughly 20% decline for large stocks in October 1929 actually wasn't market's worst month ever, but the drop incited nearly 3 years of selling.