Cumulative value (sum of principal and interest):

= principal * power (1+ interest rate, time)

The unit of time is year, which can be directly divided by two times. For example, if the principal is A 1, the interest rate is A2, the start time is A3, and the end time is A4, then the formula of the accumulated value is:

= a 1 * power (1+A2, (A4-A3)/365)

If only interest needs to be calculated, the formula of interest is:

= principal * power (1+ interest rate, time)-principal

The formula of the above example is:

= a 1 * power (1+A2, (A4-A3)/365)-A 1