Attribution from a Trust to its beneficiaries

[401_noob]

Greetings friends!

I have a question regarding the attribution from a grantor trust to the beneficiaries of the Trust. The EOB says that if a trust has an ownership interest in another organization, that interest is attributed to the beneficiaries in the trust who have a 5% or more actuarial interest in the trust, in proportion to each beneficiary's actuarial interest. 

What is actuarial interest and how is it determined? 

I found in S. Derrin Watson's Who's the Employer Q&A column, question 167- https://benefitslink.com/cgi-bin/qa.cgi?db=qa_who_is_employer&n=167, that it is determined according to IRS actuarial tables, but what table and how?

Any help would be appreciated!! 

Thanks in advance!

[Mike Preston]

See Pub. 1457 and IRC Section 7520.  Fun stuff.

[Luke Bailey]

The principle involved is the odds of each beneficiary's survival until the date when he or she will start to have an interest in distributions, how long he or she is likely to live after that, and when all this will occur (time value of money/interest). It's just math, but based on your question, unless it's a really simple situation like there are two 50% current beneficiaries who are not octogenarians, you will probably need to hire an actuary to determine all of the interests.

[401_noob]

Thank you both for your input!!