Kapitalstock

Kapitalstock, or capital stock, is a macroeconomic concept describing the cumulative value of a country’s physical capital at a given time. It includes durable produced assets used in production, such as buildings, infrastructure, machinery, equipment, and software. Financial assets, human capital, and natural resources like land are not typically counted as part of the fixed capital stock, though land improvements may be included in some accounts.

Kapitalstock is a stock variable, in contrast to flows such as investment. It evolves through gross fixed capital formation (investment) minus depreciation, also called consumption of fixed capital, plus any net price changes or retirements. The gross capital stock represents the total value of fixed assets before depreciation, while the net capital stock subtracts depreciation to reflect the assets’ remaining service life. Depreciation captures wear, aging, and obsolescence. In national accounts, valuation can be at replacement cost or original cost, depending on methodology, which affects international comparability.

Measurement commonly uses methods like the perpetual inventory approach, combining asset-by-asset data with assumed service lives and depreciation rates. Data sources include construction, equipment and software investments, asset prices, and retirement schedules. Quality changes and new asset types can complicate estimation.

Capital stock per capita or capital stock intensity (capital stock relative to labor) is a key indicator of productive capacity and development stage. Growth can result from capital deepening, raising the capital stock per worker, though diminishing returns and interactions with technology and human capital shape outcomes. Limitations include measurement error, asset heterogeneity, and underrepresentation of intangible or non-physical capital in traditional stock estimates.