The sources defines capital services per hour worked as: "the productive inputs, per period per hour worked, that flow to production from a capital asset ... the value of capital services is equal to the costs of capital services." This category includes capital stocks, oil and natural gas reserves, inventories, agricultural land and land underlying buildings.

The source adds: "the official SN calculations use an ex ante interest rate based on the internal reference rate of banks and a risk premium for calculating capital services. The model allows for profits to be made as opposed to the neoclassical model."

* The figures for 2014 and 2015 are provisional.