A practical guide for farmers and students that explains how prices for staple farm products are formed and recorded, emphasizing the interplay of supply, demand, and cost of production. It critiques existing price-registering mechanisms, including futures trading on commodity exchanges, and shows how market information and speculation influence farm returns. The author develops a ratio method to estimate cost of production for livestock and crops and applies it to hogs, cattle, milk, and grain as illustrative cases. Mathematical tools such as index numbers, correlation coefficients, and regression are presented for analyzing trends and forecasting, with discussion of their limitations. Practical teaching advice, recommended data sources, and appended tables support hands-on study and price monitoring.