It is equal to earnings less the change in capital necessary to support the business. (alephblog.com)
One has to wonder where the immense capital necessary to promote and support the animal rights groups comes from? (thedogplace.org)
Piketty applies these terms in his first fundamental law of capitalism, which is the accounting identity α = r x β, where alpha (α) equals capital's share of national income or the capital - labor split, r is the percentage rate of return on capital and Beta (β) is a ratio equal to the value of capital necessary to generate a years worth of national income. (automaticfinances.com)