If your first cash flow occurs at the beginning of the first period, the first value must be added to the NPV result, not be included in the NPV calculation.
如果第一个现金流出现在第一期的开始，则第一个值必须加到NPV结果中，而不是包含在NPV计算中。
2
When a time period is prescribed in days, months and years, the day on which the period begins shall not be counted as within the period; calculation shall begin on the next day.
规定按照日、月、年计算期间的，开始的当天不算入，从下一天开始计算。
3
This feature can help you to facilitate the calculation of your menstrual period!