[Excerpt] Multifactor productivity measures the change in output relative to the change in capital and labor inputs used to produce that output. It is designed to measure the joint influences of technological change, efficiency improvements, returns to scale, reallocation of resources, and other factors of economic growth, accounting for the effects of capital and labor. Multifactor productivity annual measures differ from BLS quarterly labor productivity (output per hour worked) measures because the former also include the influences of capital services and shifts in the composition of the workforce. Additionally, much of the source data needed to construct multifactor productivity measures are not available on a quarterly basis.