c Principal transactions

										2007	2006		2005
										£m	£m		£m
Rates related business										4,162	2,866		1,732
Credit related business										(403)	766		589
Net trading income										3,759	3,632		2,321
Gain from disposal of available for sale assets/investment securities										560	307		120
Dividend income on equity investments										26	15		22
Net gain from financial instruments designated at fair value										293	447		389
Other investment income										337	193		327
Net investment income										1,216	962		858
Principal transactions										4,975	4,594		3,179

Net trading income includes the profits and losses arising both on the purchase and sale of trading instruments and from the revaluation to market value, together with the interest income and expense from these instruments and the related funding cost.

Of the total net trading income, a £756m loss (2006: £947m gain, 2005: £498m gain) was made on securities and £640m gain (2006: £480m, 2005: £340m) was earned in foreign exchange dealings.

The net gain on financial assets designated at fair value included within principal transactions was £78m (2006: £489m, 2005: £391m) of which losses of £215m (2006: £42m gain, 2005: £2m gain) were included in net trading income and gains of £293m (2006: £447m, 2005: £389m) were included in net investment income.

The net loss on financial liabilities designated at fair value included within principal transactions was £231m (2006: £920m, 2005: £666m) all of which was included within net trading income.

The net gain from widening of credit spreads relating to Barclays Capital issued notes held at fair value was £658m (2006: £nil, 2005: £nil).