Chargeable gain calculation on encashment of an offshore bond

[bootdweller]

A recent partial encashment of an offshore bond in a discretionary trust as an individual (not encashment within/by the trust) generated a Chargable Gain statement - I was expecting it to be in line with the simple calculation of the value of cash receieved minus the original investment value of the segments encashed.
However, the stated gain is significantly higher. The bond provider's explanation is that the gain includes the rolled up historical fees incurred during the lifetime of the investment.
Is this normal? - I can't find any reference to chargable gains including historical fees in their calculated value.

[someone]

Don't know the details but it sound plausible.

If you have a bond that grows by 100 per year for 10 years but 10 per year is "removed" for fees then your final value will be 900 greater that the initial investment but the total gain will be 1000, just that 100 of it went in fees.