Let's have a more detailed look at the trading securities of this bank, the largest single asset line on the balance sheet and how this value is arrived at.

The biggest consideration for these trading assets shown at fair value is how the fair value has been determined.

Looking at the table, you can see from each line item that there is a good spread over all of the different types of financial instruments.

However, if we were to pick out a focus, it would seem that this bank has focused more on the following instruments, government agency, bonds, both US and non-US corporate bonds, equities, and derivatives.

We can also see from this note that the assets are split into three levels, one, two, and three.

This refers to the way in which the fair value of the asset has been determined under the fair value hierarchy.

If an asset being fair valued is quoted in an active market, it is said to sit at level one of the hierarchy.

This provides us with the most confident indicator of fair value.

If an active market is unavailable for a security, we're at level two with the fair valuation being arrived at by referring to similar assets.

If we can't make reference to similar assets, then we're at level three, which requires us to build a discounted cash flow model to arrive at the fair value.

Clearly, this gives us the least confidence over the valuation.

For this bank. The fair value has been determined using level one for 355 billion or around two thirds of their trading cash instruments in total with level two being used for the majority of the remainder.

Looking again at the notes, we can see that the trading assets have resulted in gains and losses, principally recorded under market making, and if we turn to the right of the screen, we have the top part of this bank's income statement.

This gives us some context for the significance of the bank's market making activity.

In fact, we can see that it makes up 40% of their non-interest revenues a word of caution. However, at this level, it's quite difficult to do any further meaningful profitability analysis, as many of the transactions may well be connected to a wider set of transactions or related to hedging activities.

But hopefully we can get the idea that this is connected to the market making activities, which is both owning instruments on a long-term basis, and also short selling.