(a) Insurers shall invest in or lend their funds on the security of, and shall hold as invested assets, only eligible investments as prescribed in this article.

(b) Eligibility of an investment shall be determined as of the date of its making or acquisition.

(c) Any investment limitation based upon the amount of the insurer's assets or particular fund shall relate to such assets or funds as shown by the insurer's annual statement as of December 31 of the year preceding the date of acquisition of the investment by the insurer or as shown by a current financial statement resulting from merger of another insurer, bulk reinsurance, or change in capitalization.