To use financial modeling to plan for contingencies in a program, you need to define the scope and objectives of your financial model, collect and validate data, design and develop your model, test and validate it for accuracy, completeness, logic, and functionality, perform sensitivity and scenario analysis, and communicate and use your model to support decision making. Firstly, you should consider the main questions or hypotheses you want to test or explore, as well as the key variables and parameters you want to include or exclude. Additionally, you need to ensure that your data is accurate, reliable, consistent, and relevant for your program. When designing the model, choose a suitable level of detail, complexity, and flexibility. Then select the appropriate methods and formulas to calculate financial metrics. Afterward, check your financial model for errors, gaps, inconsistencies or anomalies. Subsequently, identify and vary the key factors that may affect the program's financial performance. Furthermore, create different scenarios and contingencies that may occur during the program's lifecycle. Finally, present your financial model to stakeholders and use it to inform contingency planning.