policies of insurance or reinsurance where the initial premium is subject to variation depending upon claims experience (see also Burning cost).

Most insurance companies issuing investment bonds and unitised funds offer a variety of investments linked to property, equity, managed and fixed-interest funds, and sometimes cash or gilt funds. In return for a fee most will permit the holder to switch his investment from one fund to another. As the money remains invested in the same life policy liability to tax does not arise as happens when shares are sold.