The Gross Domestic Product (GDP) is the broadest measure of aggregate economic activity and encompasses every sector of the economy. It is the monetary value of all the finished goods and services produced within a country’s borders in a specific time period, though GDP is usually calculated on an annual basis. It includes all of private and public consumption, government outlays, investments and exports less imports that occur within a defined territory.

GDP = C + G + I + NX

where:

C” is equal to all private consumption, or consumer spending, in a nation’s economy
G” is the sum of government spending
I” is the sum of all the country’s businesses spending on capital
NX” is the nation’s total net exports, calculated as total exports minus total imports. (NX = Exports – Imports)

GDP is commonly used as an indicator of the economic health of a country, as well as to gauge a country’s standard of living. Critics of using GDP as an economic measure say the statistic does not take into account the underground economy – transactions that, for whatever reason, are not reported to the government. Others say that GDP is not intended to gauge material well-being, but serves as a measure of a nation’s productivity, which is unrelated.

In the US, a quarterly figure is released by the US Department of Commerce’s Bureau of Economic Analysis.

Data are available in nominal and real (inflation-adjusted) dollars, as well as in index form. Economists and market players always monitor the real growth rates generated by the GDP quantity index or the real dollar value. The quantity index measures inflation-adjusted activity, but we are more accustomed to looking at dollar values.

Individuals purchase personal consumption expenditures — durable goods (such as furniture and cars), nondurable goods (such as clothing and food) and services (such as banking, education and transportation).

Private housing purchases are classified as residential investment. Businesses invest in nonresidential structures, durable equipment and computer software. Inventories at all stages of production are counted as investment. Only inventory changes, not levels, are added to GDP.

Net exports equal the sum of exports less imports. Exports are the purchases by foreigners of goods and services produced in the United States. Imports represent domestic purchases of foreign-produced goods and services and must be deducted from the calculation of GDP.

Government purchases of goods and services are the compensation of government employees and purchases from businesses and abroad. Data show the portion attributed to consumption and investment. Government outlays for transfer payments or interest payments are not included in GDP.

The GDP price index is a comprehensive indicator of inflation. It is typically lower than the consumer price index because investment goods (which are in the GDP price index but not the CPI) tend have lower rates of inflation than consumer goods and services.

When gross domestic product expands more (less) rapidly than its potential, bond prices fall (rise). Healthy GDP growth usually translates into strong corporate earnings, which bode well for the stock market.

The four major categories of GDP — personal consumption expenditures, investment, net exports and government — all reveal important information about the economy and should be monitored separately. One can thus determine the strengths and weaknesses of the economy in order to assess alternatives and make appropriate financial investment decisions.

Economists and financial market participants monitor final sales — GDP less the change in business inventories. When final sales are growing faster than inventories, this points to increases in production in months ahead. Conversely, when final sales are growing more slowly than inventories, they signal a slowdown in production.

It is useful to distinguish between private demand versus growth in government expenditures. Market players discount growth in the government sector because it depends on fiscal policy rather than economic conditions.

Market participants view increased expenditures on investment favorably because they expand the productive capacity of the country. This means that we can produce more without inciting inflationary pressures.

Net exports are a drag on total GDP because the United States regularly imports more than it exports, that is to say, net exports are in deficit. When the net export deficit becomes less negative, it adds to growth because a smaller amount is subtracted from GDP. When the deficit widens, it subtracts even more from GDP.

Gross domestic product is subject to some quarterly volatility, so it is appropriate to follow year-over-year percent changes, to smooth out this variation.

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