Meanwhile, pay at asset management firms has been rising for the last decade, increasing by one fifth over the same period to reach $263,000 in 2014.
"Pay at investment banks is taking up a shrinking portion of a shrinking pot. At asset management firms, it is taking a constant portion of a growing one," said founder and managing director of New Financial, William Wright.
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"Over the past decade, pay at asset management firms has almost caught up with pay at investment banks. In 2004 average compensation cost per employee was just over half that at investment banks. We estimate that it rose to 92 percent in 2014 and may soon overtake average pay at investment banks," Wright said.
While investment banker pay has taken a hit in recent years, there is now some evidence that compensation packets for the most senior staff is on the rise again, the report found,
The average pay for 6,000 so-called code staff -- senior management and "risk takers" -- increased by 6 percent in 2013 from the year before to just under $2 million, while falling 2 percent for all staff across the rest of the industry. Average pay in the investment banking industry climbed marginally in 2014 when compared with 2013.
"At some firms the fall in pay has been even steeper: average pay per employee at Goldman Sachs has tumbled by more than 40 percent since 2007 from a high of $661,000. At JPMorgan, the largest corporate and investment bank in the world, average pay has flatlined through the crisis," Wright said.