The study looked at how financial shocks affect business investment in the U.S. They found that these shocks only account for a small part of investment changes, mainly because different types of companies react differently. When financially constrained companies cut back on investment, financially stable companies increase theirs, balancing out the overall impact. If all companies were the same, financial shocks would have a much bigger effect on investment. This shows that understanding the differences between companies is crucial for understanding how financial shocks affect the economy.