There are different economic explanations or theories for the business cycle that seek explaining how the economy's output level, average price level, and unemployment / employment rates change together or co-vary. Explain why economists seek these explanations and why these explanations when adopted by others for their use in business planning or legislating macroeconomic policy is important to you in your personal and working lives. Note there does not exist to date a single macroeconomic theory that explains the full extent of possible co-variation between the variables Real GDP, the average price level, and unemployment / employment.