(IV) The resultant sum as determined under clause (III) shall be diminished by the value, as ascertained under clause (II), of any investments the income from which is not taken into account in computing the profits of the business and any moneys not required for the purpose of the business, insofar as the aggregate of such investments or moneys exceed the amount of the borrowed moneys which under clause (III) are required to be deducted in computing the capital.