fee revenue and other revenue. Prior periods have been reclassified. See "Reporting Changes" beginning on page 9 for additional information. KEY DRIVERS Total revenue includes corporate treasury and other investment activity, including hedging activity which offsets between fee and other revenue and net interest expense. Other revenue decreased year-over-year and sequentially, primarily reflecting an impairment of a renewable energy investment. The sequential decrease in other revenue was partially offset by a loss on a sale of a business recorded in 4Q20. Noninterest expense increased year-over-year primarily reflecting higher staff expense. The sequential decrease primarily reflects real estate charges and severance expense both recorded in 4Q20, partially offset by higher other staff expense.