Investment allowance for new ships, aircraft and qualifying machinery permits an additional deduction subject to opt-out and exclusions. Amendment inserts an investment allowance in section 32 permitting an assessee in ship/aircraft operations, specified manufacturing or power businesses, or qualifying small-scale undertakings to claim an additional deduction equal to twenty per cent of the actual cost of specified new ships, aircraft, machinery or plant in the year of acquisition or installation, subject to exclusions (office/residential installations and assets eligible for development rebate), an opt-out declaration mechanism, and detailed definitions for 'new' assets and small-scale status.