Ship depreciation rule amended to reduce the applicable percentage for certain acquisitions and clarify reserve-related deduction treatment. Amendment to section 34 inserts a proviso substituting a lower depreciation percentage for ships acquired after a specified date, treating such substitution as if originally enacted; and adds an Explanation declaring that the deduction referred to in section 33 is not to be denied merely because the amount debited to profit and loss and credited to the reserve exceeds the profit of the relevant previous year when computed without that debit.