(1) Except to the extent included in the augmented estate under section 15-11-204 or 15-11-206, the value of the augmented estate includes the value of:

(a) Property that was owned by the decedent's surviving spouse at the decedent's death, including:

(I) The surviving spouse's fractional interest in real property held in joint tenancy with the right of survivorship created during the marriage to the decedent, except as provided in section 15-11-208, and the surviving spouse's fractional interest in personal property held by the surviving spouse in joint tenancy with the right of survivorship;

(II) The surviving spouse's ownership interest in property or accounts held in POD, TOD, or co-ownership registration with the right of survivorship; and

(III) Property that passed to the surviving spouse by reason of the decedent's death but not including the spouse's right to family allowance, exempt property, or payments under the federal social security system after the decedent's date of death; and

(b) Property that would have been included in the surviving spouse's nonprobate transfers to others, other than the spouse's fractional and ownership interests included under subparagraphs (I) and (II) of paragraph (a) of this subsection (1) had the spouse been the decedent.

(2) Property included under this section is valued at the decedent's death, taking the fact that the decedent predeceased the spouse into account, but for purposes of subparagraphs (I) and (II) of paragraph (a) of subsection (1) of this section, the values of the spouse's fractional and ownership interests are determined immediately before the decedent's death if the decedent was then a joint tenant or a co-owner of the property or accounts. For purposes of this subsection (2), proceeds of insurance that would have been included in the spouse's nonprobate transfers to others under section 15-11-205 (1)(d) are not valued as if he or she were deceased.

(3) The value of property included under this section is reduced by enforceable claims against the surviving spouse.