Imagine you have prepared a plan for John and Patricia. John is 57 years old, and Patricia is 56 years old. They retire at age 65. The inputs are:

Planned spending life phases

One-off expenses

Income sources

Total portfolio allocation

Total Balance = £438,426

At 92 years old, there's a 52% chance one member is still alive. By 99 years old, it's only 13%.

And the question is, how long do they want to plan for? Do they want to plan for that 13% or a 10% chance of survival?

You can look at how likely the portfolio will be sustained at a particular age. So at the age of 76, based on all of the historical scenarios that this specific plan has been tested against, there is a 99% probability that this portfolio will survive.

For this plan, when they have a 50% chance of survival, their portfolio has a 97% chance of lasting. When they have a 10% chance of survival, the portfolio has a 77% chance.

If someone has a health issue, like smoking history, we can adjust the plan to reflect that. We can also see how likely they are to run out of money and remain alive.

But there are other ways of looking at how long to plan for. The green line shows there is only a 77% chance of the portfolio surviving until the age of 100. But actually, the chance of running out of money and one member of the couple still alive is much less. We can see this in the table below the longevity chart.

For example, at 97 years old, there's a 37% chance they'll run out of money, but only an 8% chance they'll run out of money and still be alive. This means they might want to plan to have their money last until an earlier age, so they can spend more while they're still alive.