In saying that it is a price-based target, it is important to remember that in maintaining the threeyear yield target the Bank is still buying the quantities of bonds required to achieve that. Those purchases have their effect on maintaining the three-year yield at the target but they also have the same portfolio substitution effect as the quantitative easing programs of other central banks.
A key driving force of sustainable development is the harnessing of positive externalities to private sector activities and the minimising of negative externalities. Positive externalities occur when social rates of return to investment exceed the purely private rates of return.