An insurance policy is open, running, or valued, and these terms are defined as follows:

1.    An open policy is one in which the value of the thing insured is not agreed upon but is left to be ascertained in case of loss.

2.    A running policy is one which contemplates successive insurances and which provides that the object of the policy may be defined from time to time, especially as to the subjects of insurance, by additional statements or endorsements.

3.    A valued policy is one which expresses on its face an agreement that the thing insured must be valued at a specified sum.