Total factor productivity

In economics, total-factor productivity (TFP), also called multi-factor productivity, is usually measured as the ratio of aggregate output (e.g., GDP) to aggregate inputs. Under some simplifying assumptions about the production technology, growth in TFP becomes the portion of growth in output not explained by growth in traditionally measured inputs of labour and capital used in production. TFP is calculated by dividing output by the weighted geometric average of labour and capital input, with the standard weighting of 0.7 for labour and 0.3 for capital. Total factor productivity is a measure of productive efficiency in that it measures how much output can be produced from a certain amount of inputs. It accounts for part of the differences in cross-country per-capita income. For relatively small percentage changes, the rate of TFP growth can be estimated by subtracting growth rates of labor and capital inputs from the growth rate of output. Technology growth and efficiency are regarded as two of the biggest sub-sections of total factor productivity, the former possessing "special" inherent features such as positive externalities and non-rivals which enhance its position as a driver of economic growth. Total factor productivity (TFP) is often considered the primary contributor to GDP growth rate. Other contributing factors include labor inputs, human capital, and physical capital. Total factor productivity measures residual growth in total output of a firm, industry or national economy that cannot be explained by the accumulation of traditional inputs such as labor and capital. Since this cannot be measured directly the process of calculating derives TFP as the residual which accounts for effects on total output not caused by inputs. It has been shown that there is a historical correlation between TFP and energy conversion efficiency. Also, it has been found that integration (among firms for example) has a causal positive impact on total factor productivity.