define profit margins Interest rate, in the form of expression, refers to the ratio of the amount of interest to the total amount of borrowed capital in a certain period of time.  the interest rate is the interest level per unit time of the unit currency, indicating the interest rate. Economists have been looking for a theory that can fully explain the structure and change of interest rates. Interest rates are usually controlled by the central bank of the country and administered by the federal reserve board in the United States. Today, interest rates are one of the important tools for macroeconomic regulation. The social profit generated by enterprise activities is the addition of economic profit or the external economic effect of the activity. Companies may make significant monetary profits, but external economic effects often result in negative results, and substantial social profits may be minimal. Such as the industrial revolution, the mass production of the factory is low cost and price of product, but in order to earn maximum profit, factory owners and lower production costs, lead to the low wages of child labor, as well as improper handling industrial waste or contaminants and other social burden. In management, the plan has a double meaning, one is the work plan, is refers to according to the analysis of external environment and internal conditions, put forward in the future a certain period of time to achieve organizational goals and achieve the goal of the solution way. Secondly, plan form, it is to point to in words and index within the organization of the form of expression and organization of different departments and different members of a certain period of time in the future about the management of the direction, content and way to arrange events. The important thing to keep in mind when being sued by plastic card company or junk debt buyers is when they do not have proof that will otherwise prove how the debt is yours, they do not have a case. For junk debt buyers, you are in luck since these agencies don't have the required documents that might prove you possess the debt, like a signed contract between you and the original creditor, because they documents are never released with the original creditor.