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The biggest American banks report earnings this week, and they will probably be hampered by weaker economic growth and lower interest rates. The Federal Reserve cut interest rates in July and again in September, making it more difficult eke out returns on loans.

The dour earnings expectations mark a change from the previous quarter, when big banks returned fat profits despite worries about an economic downturn in the United States.

Tuesday is the big day. Investors will hear from Citigroup, Goldman Sachs, JP Morgan Chase and Wells Fargo before the opening bell. Bank of America follows on Wednesday.

"We are in challenging times for large banks, where the pulse of investor activity may often impact the large banks asset and wealth management units," CFRA Research's Kenneth Leon wrote in a research note.

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