According to the latest data released by the U.S. Department of Transportation, the number of driving miles (VMT) in October 2017 is 268 billion miles, up 0.8 percent year on year and 0.2 percent month-on-month. According to the data, total vehicle mileage is expected to reach 2.685 trillion miles in 2017. Historical costs differ from current values The selection and evaluation of transactions. Engaging in foreign exchange investment, one must choose a profitable trading method. Here are some factors to consider in trading options. This approach periodically revised future plans based on the implementation of the plan and changes in the environment, and moved forward over the period to integrate short-term and medium-term plans organically. As it is difficult to accurately predict the future of the plan work affect organizational survival and the development of economy, politics, culture, technology, industry, customers and other factors change, and as the extension of planning period, the uncertainty is greater and greater. Therefore, the implementation of a planned implementation of a mechanical, or mechanical, and static execution of a strategic plan by a number of years ago may result in significant errors and losses. Rolling planning can avoid the consequences of this uncertainty. The specific approach is to make plans in a very short and thin way.