10.22 The appetite for project related bonds can move greatly over relatively short periods of time. Institutions may be looking for different types of assets at different times depending on the amount they have to invest, the return they require and what other assets are available in the market at the time. This makes pricing the margin on the bond difficult. The margin is not just, as on a bank deal, the appropriate credit margin for the underlying risks in the project, but also an element of market pricing and demand.