Economic growth is an increase in the goods and services produced by an economy over time, usually measured by the percentage change in real gross domestic product (GDP). “Real” means adjusted for price changes, so growth reflects increased production rather than inflation alone. A central subject of macroeconomics, growth encompasses both short-term changes in output and the long-term expansion of productive capacity. It is distinct from improvements in welfare, although the two can be related. (imf.org)
Measurement and interpretation
GDP measures the value of final goods and services produced within an economy during a specified period. Within national accounts, it can be calculated from production, expenditure, or income. Nominal GDP values output at current prices; real GDP removes the effects of changing prices, using price and volume measures related to indicators such as the GDP deflator. (imf.org)
If denotes real GDP in period , its growth rate is:
For example, an increase from 100 to 103 represents 3 percent growth. Sustained growth compounds: output growing at a constant 2 percent annually would approximately double in 35 years.
Total output and output per person answer different questions. GDP per capita divides GDP by population; its growth indicates whether average production is increasing faster than population. It does not show how income is distributed. International comparisons often use purchasing power parity to account for differences in price levels rather than relying solely on market exchange rates. (imf.org)
Growth rates also depend on the comparison period. Quarterly, annual, and longer-term averages describe different aspects of performance. A temporary increase during recovery need not imply a comparable increase in the economy’s underlying long-run growth rate. (imf.org)
Sources of growth
Output can expand because an economy uses more inputs or uses existing inputs more effectively. Additional workers and working hours increase labor input. Investment enlarges the stock of machinery, buildings, and infrastructure, although some investment replaces assets that have worn out rather than adding productive capacity. Productivity—output relative to inputs—determines how effectively those resources generate production. (imf.org)
Human capital comprises people’s knowledge, skills, and experience. Education and training can improve workers’ capabilities and their ability to use new technologies. Technological change and innovation can introduce new products, more efficient production processes, and improved organization. Their economic effects depend partly on adoption and diffusion, not simply invention. (worldbank.org)
Growth accounting separates measured output growth into contributions from capital, labor, and total factor productivity (TFP). TFP captures the portion not explained by measured input growth. It is not a pure measure of technology: it can also reflect resource allocation, organizational improvements, omitted inputs, and measurement error. Consequently, a statistical decomposition identifies proximate contributions but does not, by itself, establish their underlying causes. (imf.org)
Major theoretical approaches
The Solow–Swan model, developed in the 1950s, explains growth through capital accumulation, labor-force expansion, and technological progress. With diminishing returns to capital, adding machinery while holding other conditions constant produces progressively smaller increments to output. In the standard model, a higher saving rate raises the long-run level of output per worker but does not permanently raise its growth rate; sustained growth per worker requires technological progress. (nobelprize.org)
The model supports conditional convergence: economies further below their own long-run paths may grow faster when relevant structural conditions are comparable. It does not predict that every poorer economy must catch up with every richer one. (nobelprize.org)
Endogenous growth theory instead explains technological progress and knowledge accumulation within economic models. Research incentives, human capital, and knowledge spillovers can influence long-run growth. Ideas can be used by multiple producers, while innovators may need mechanisms allowing them to recover development costs. Schumpeterian approaches emphasize creative destruction, in which new products and technologies displace older activities. These approaches direct attention to incentives and institutions as well as aggregate investment. (nobelprize.org)
Structural transformation and institutions
Growth frequently accompanies structural transformation: changes in the distribution of employment and production across agriculture, manufacturing, and services. Moving resources from lower-productivity to higher-productivity activities can raise aggregate output, alongside productivity improvements within each sector. A sector’s declining employment share therefore need not mean its production is falling. (documents1.worldbank.org)
Trade and participation in global value chains can connect producers to larger markets, technology, and specialized knowledge. Institutional arrangements also affect investment and production. Governance research examines how institutional quality, including the rule of law, relates to economic performance, while recognizing that growth involves interacting economic and social conditions rather than a single universal mechanism. (worldbank.org)
Growth, well-being, and sustainability
GDP growth is not a comprehensive measure of quality of life. It does not directly indicate income distribution, leisure, security, or environmental quality, and it excludes much unpaid household work. Rising average output can coexist with unevenly distributed gains. Broader assessments therefore supplement GDP with social and distributional indicators. (imf.org)
Sustainable development additionally concerns whether present economic activity preserves resources and opportunities for the future. Pollution and resource depletion can impose external costs that conventional GDP does not adequately capture. Environmental accounts and well-being frameworks examine these alongside output, distinguishing increased production from changes in the natural and social assets supporting future prosperity. (oecd.org)