Is there a way to calculate only the first row of a table?

thank you in advance

17 minutes ago, Matthew R White said:

Is there a way to calculate only the first row of a table?

I don't know what that means. Why don't you elaborate with an example and - most importantly - explain why this would be necessary.

I have a table called Premiums and the initial premium is always the first created record in this table. Throughout the year more records are added to this table as premium is subtracted or added.

I’m looking to summarize the initial premium in the first row for all my records to show total initial premiums

Does this make more sense?

6 minutes ago, Matthew R White said:

Does this make more sense?

Just barely. Is there a parent table to these premiums? A calculation field in such table would get the data from the first related record in Premiums - which, if the relationship is unsorted, would be the first related record in creation order. And you could use a summary field (again, in the parent table) to get the total for the entire found set (of the parent table). All unstored, so it won't be fast. 

Makes you think if the initial premium isn't really more an attribute of the parent object than it is a sibling of the subsequent premiums.