If it has done nothing else, the explosive growth of the American financial community in the past few years demonstrated that the members of that community are very talented people. Demonstrate a need and someone will come up with a way to satisfy it; and sometimes they come up with answers before the questions even have been asked.

Case in point: Last fall (Sept. 3), I wrote about the impact of the Tax Reform Act of 1984 on no-interest interfamily demand loans. For all practical purposes, the new rules did away with such loans as a technique for switching income-tax liability from a high-bracket to a low-bracket family member.

I suggested then that a Clifford trust might be used as an alternative technique. But a Clifford trust is not a do-it-yourself project; the trust instrument is a legal document that should be prepared by an attorney.

Which leads me to a new product called "The University Trust," introduced last fall by Citibank. The University Trust is essentially a pre-established format for Clifford trusts that you may initiate simply by filling out a couple of forms and sending them with a check to Citibank.

(In fact, the structure permits the establishment of other types of trusts, too; but the subject for today is the use of a Clifford trust for accumulating college funds for minor children by using a tax-shifting technique.)

The rules for University Trust I -- Citibank's Clifford trust vehicle -- follow the rules for Clifford trusts in general. You deposit cash or income-producing property in the trust; the income goes to the beneficiary (the low-taxed child, in this case). At the end of the trust period -- which must be at least 10 years and a day -- the principal is returned to the donor without any tax consequences. (Citibank has set its minimum term at 10 years and one month.)

You may not add additional gifts to the trust after its establishment. Later additions would have the effect of extending the period for at least 10 years and a day after the last gift, and would complicate the record-keeping. But you may set up more than one trust, for the same or different beneficiaries.

The trust department at Citibank will invest the funds in one of their "Collective Investment Funds" (pooled trust funds), certificates of deposit or Treasury or U.S. instrumentality obligations. They will provide any statements required for record-keeping or tax purposes.

Naturally, there is a fee for this fiduciary service. The current fee is 1 percent of the assets in the trust (deposited principal plus accumulated earnings), with a minimum annual fee of $250. There is no charge for opening the account.

You must deposit at least $10,000 into the trust. As a practical matter, I think a larger amount would be advisable, because of the minimum annual fee. If the principal earns 10 percent, that $250 represents 25 percent of the first year's earnings.

That ratio goes down as earnings accumulate, however; and -- depending on your tax bracket -- even this minimum amount may pay if it lets you shift tax liability to your child, who may have little or no tax to pay on the trust earnings.

One caveat: Like any Clifford trust, use of any of the earnings for "support" of the child -- that is, for any of those things for which you are responsible under state law -- would return the tax liability to you and negate the tax advantages of the trust technique.

The legal experts at Citibank have done the necessary research to be sure their trust instruments satisfy the requirements of the law. If you have any doubts, of course, you should consult your own attorney for guidance.

The rate of interest charged by the IRS on late payments and estimating deficiencies has been raised to 13 percent, up from the 11 percent rate that applied from July 1 to Dec. 31, 1984.

This increase may seem strange in view of the drop in interest rates over the past few months. But by law, the rate for each six-month period is based on the average prime rate for the six-month period from the preceding April 1 to Sept. 30 -- and the prime was higher then. The next change will take effect July 1, based on the average prime rate from Oct. 1, 1984, to March 31, 1985.