JPMorgan's net interest income accounts for between 45-50% of the bank's total revenues for any given quarter, which is why even slight changes to the bank's net interest margin ( NIM ) figure have an amplified effect on its earnings. The Fed's decision to hold interest rates at near-zero levels since the economic downturn of 2008 resulted in NIM figures across banks to shrink each quarter. JPMorgan mirrored this trend, with the NIM figure falling from a little over 3% in 2010 to a low of 2.07% in Q1 2015.