Investment banking revenues aren't likely to reach 2007 levels for another decade, according to a wide-ranging report on the future of the industry, which asserts that the bulk of the recent revenue decline is structural.

The report, published by Deutsche Bank research analyst Matt Spick and strategist Bilal Hafeez, looks at whether investment banking revenues are undergoing a cyclical or structural depression, the progress that banks have made on cutting costs and which bank business models are proving most successful.