Double-Counting of Investment*
研究发现国民收入账户对投资进行了双重核算，导致GDP和国民收入高估了可持续消费。基于永久收入调整后，美国劳动收入份额相对稳定，而非GDP显示的下滑趋势。
Abstract The national-income accounts double-count investment, which enters once when it occurs and again in present value as rental income on added capital. The double-counting implies that GDP and national income overstate sustainable consumption. An alternative measure, ‘permanent income,’ equals consumption in the steady state but deviates from consumption outside of the steady state because expensing of gross investment applies to the long-run flow, not the current value. The permanent-income perspective substantially affects measured factor-income shares. When computed in relation to permanent income, the U.S. labor-income share has been reasonably stable, in contrast to the declining share based on GDP.