1 Rise in shares, credit and commodities Investment banks have large trading rooms, sometimes hosting as many as 700 traders, buying and selling stocks, bonds or commodities such as oil, gas or even pork bellies.
Markets have risen sharply in recent months, encouraging more trading - a trend that has been more apparent since March, when investors started perceiving the worst of the credit crunch was over.
Oil has gained 27% this year, and equity markets have also rallied. The FTSE 100 index has gained 21% since the end of March, while in the US the Dow Jones Industrial Average has surged 22.8%, according to Bloomberg data.
2 Less competition means higher fees The credit crunch has sunk some investment banks, reducing competition in the UK market by about 35%. Fewer players in the market can now charge more for their services. Average fees to raise money for a company by selling shares have risen to 3.5% of the size of the deal so far this year, from 2.9% in 2008, according to Bloomberg data.
3 Plenty of work Companies and governments are using debt. With banks around the world pressured to shrink their balance sheets, companies and governments need to tap other markets to raise funds. Global bond sales rose 27% in the first three months of the year to a combined $2.5tn, the most in at least a decade, according to Bloomberg data.
The UK government plans to raise £220bn through gilt sales this year, in part to finance the bail out of Royal Bank of Scotland and HBOS - now part of Lloyds. Companies have also tapped the markets by offering bonds - using the proceeds to pay back their now very expensive bank debt.
4 Safety assured In order to calm to the panic that spread in the markets after the collapse of Lehman Brothers in September last year, governments such as Britain's offered to guarantee bank bond sales. A number of other government schemes have propped up the banking system. Banks also know that ministers will not allow them to fail or for depositors to lose money.
5 Accounting Analysts have indicated that new European accounting rules, introduced in October, are helping banks hide the true effect of the credit crunch. Under these rules, banks can avoid having to put a market price to some of their most toxic assets. Barclays, RBS and Deutsche Bank have used the new guidance, and so reduced their potential write-downs.
Copyright Speakers Corner 2016