31-1-106. Legal interest. (1) Except as otherwise provided by the Uniform Commercial Code, 31-1-111, and 31-1-112, unless there is an express contract in writing fixing a different rate or a law or ordinance or resolution of a public body fixing a different rate on its obligations, interest is payable on all money at the rate of 10% a year after it becomes due on:
(a) any instrument of writing, except a judgment;
(b) an account stated;
(c) money lent or due on any settlement of accounts from the date on which the balance is ascertained; and
(d) money received for the use of another person and detained from that person.
(2) In the computation of interest for a period of less than 1 year, 365 days constitute a year.