In economics, the poverty line is a widely accepted benchmark for deciding the eligibility for various government assistance including food stamps, Medicaid and Supplemental Social Security income (SSI.) The measure of how poor a family is considered to be, as determined by this line, often varies across different regions, as it has historically varied according to location and underlying economic indicators. A standard deviation, which is the difference between actual values of income in any particular period and the theoretical maximums, is used to adjust for the varying sample sizes. Because of this potential for error, the actual and maximum values are often adjusted. This standard deviation is also used in analyzing the relationship between demand and supply, which is an important concept to management in any industry. The PLC is commonly used in Warehouse Inventory Management and Procurement, which is one of the largest and most important components in supply chain management.
This text available from the US Department of Labor, Economic Research Service, provides a comprehensive explanation of the PLC and describes the relationship between supply chain management decisions and the PLC text available from the USDOT. This text is one of many tools that are required for effective decision making in the food retailing, food service, and food manufacturing industries. Another important note regarding the use of these references is that they are only meant as guides and should not be used as references in the making of policy or as a definition of the meaning of the PLC.
There are numerous other statistical analysis reports available from the USDA. One such report is entitled "The Food pyramid program helps Americans improve nutrition", which provides a detailed account of the current US food supply chains. It includes an analysis of how changes in the food supply chain management can affect food quality standards, consumer safety, and food prices. Another report is available from the USDA entitled "USDA's food pyramid program: an integrated program for improving the nutritional quality of the nation's food supplies". This report provides detailed information on the impact of the food source protection requirements and offers guidelines for creating and maintaining balanced food supply chains.