Hugh Barker

it is meaningless to describe any of these goods as having value in themselves without referring to who is valuing them and what they might exchange for them

The only way you should value an asset is by considering its current value and comparing this to your other options: most of what has happened in the past is irrelevant. The trajectory of its past value may, of course, give us some information about the future trajectory, though as the adverts always say, ‘past performance is no guarantee’. While the aim should always be to sell an asset for more than you paid for it, refusing to sell at a loss can be more damaging than accepting the loss and moving on

The rule is to divide 72 by the rate of growth (or the interest rate, for savings and investments): the result gives you the number of periods it will take for the initial investment to be doubled. For instance, for an interest rate of 9% a year, we divide 72 by 9 and get 8 years. The actual time it would take money to double at 9% is 8.043 years (see Figure 5), so this is reasonably accurate