Gross Domestic Product The gross domestic product of a country is a measure of all of the finished goods and services that a country generated during a given period. The GDP calculation is split into four categories: private consumption, government spending, business spending and total net exports. GDP is considered the best overall measure of the health of a country's economy, with GDP increases signaling economic growth. The healthier a country's economy is, the more attractive it is to foreign investors, which in turn can often lead to increases in the value of its currency, as money moves into the country. In the U.S., this data is released by the Bureau of Economic Analysis once a month in the third or fourth quarter of the month.Retail Sales Retail sales data measures the amount of sales that retailers make during the period, reflecting consumer spending. The measure itself doesn't look at all stores, but, similar to GDP, uses a group of stores of varying types to get an idea of consumer spending. This measure also gives market participants an idea of the strength of the economy, where increased spending signals a strong economy. In the U.S., the Department of Commerce releases data on retail sales around the middle of the month.