As an
economic term, investment refers solely to the addition of
capital stock of the
economy. This can be through purchasing of
capital goods or improving
human capital. Because of this it cannot be carried out by
households but by the
public and
private sectors. Using this
definition putting
money into a
bank account is
saving and not investment.
Investment can be measured in two forms - gross and net. Gross investment is a measure of the amount spent while net investment includes depreciation of capital stock.