Underground economy is a term that defines those individuals and businesses that deal with cash or use other schemes to hide their activities and their  tax liability from government licensing, regulatory, and taxing agencies. The part of a country's economic activity that is unrecorded and untaxed by the government. The underground economy can be beneficial can be characterized as "Black Market" which goods and services are bought illegally. For example, the selling of drugs on streets or buying untaxed cigarettes and alcohol. Not many people think of illegal street vendors or unlicensed businesses as a contributor to our economy. In some ways they are beneficial. Such as adding jobs, increasing sales, and improving the lives of hundreds of humans. In other ways the hidden economy can be seen as detrimental. All the economic activity basically "flies under the radar of government". Unregistered, unregulated, untaxed, but not criminal. I hate guns.

Many economists struggle to predict the business cycle each day.  Business cycles are difficult to predict, but certain measures,also known as indicators, can provide signals to corporate leaders.Such as Wall Street investors, economists and government officials about the onset or progress of business cycles.The term "bull market" is often used to refer to the stock market, but can be applied to anything that is traded, such as bonds, currencies and commodities. The term “bear market” a market that appears to be in a long-term decline. Leading to this is recession and depression. A recession is a period of temporary economic decline during which trade and industrial activity are reduced.Mostly identified by a fall in Gross Domestic Product  in two successive quarters.“Depressions are like plagues: devastating, rare, and only dimly understood after the fact. The occur when the economy’s normal recuperative mechanism fails to engage; the bungee cord breaks.” (4,Ip) A depression is known as severe and prolonged downturn in economic activity. In economics, a depression is  defined as an extreme recession that lasts two or more years. A depression is impacted by economic factors for example substantial increases in unemployment, a drop in credit, diminishing output, bankruptcies, reduced trade and commerce, and sustained currency values.Economic growth is the increase in a country’s standard of living over time. Growth economists study how living standards differ across countries as well as across time. Many of this changed from the twentieth century to now in 2015.