In this subtitle the following words have the meanings indicated. “Common trust fund” means a fund that a trust company maintains under this subtitle solely for the collective investment of money held by the trust company as fiduciary. “Fund plan” means a written plan for the establishment and administration of a common trust fund. “Trust company” includes a national banking association that has powers similar to those given to a trust company under the laws of this State. “Valuation date” means a date as of which a trust company determines the value of the assets in a common trust fund that it administers.