(1) Except as provided in section 13-21-101, C.R.S., when there is no agreement as to the rate thereof, creditors shall receive interest as follows:

(a) When money or property has been wrongfully withheld, interest shall be an amount which fully recognizes the gain or benefit realized by the person withholding such money or property from the date of wrongful withholding to the date of payment or to the date judgment is entered, whichever first occurs; or, at the election of the claimant,

(b) Interest shall be at the rate of eight percent per annum compounded annually for all moneys or the value of all property after they are wrongfully withheld or after they become due to the date of payment or to the date judgment is entered, whichever first occurs.

(2) When there is no agreement as to the rate thereof, creditors shall be allowed to receive interest at the rate of eight percent per annum compounded annually for all moneys after they become due on any bill, bond, promissory note, or other instrument of writing, or money due on mutual settlement of accounts from the date of such settlement and on money due on account from the date when the same became due.

(3) Interest shall be allowed as provided in subsection (1) of this section even if the amount is unliquidated at the time of wrongful withholding or at the time when due.

(4) Except as provided in section 5-12-106, creditors shall be allowed to receive interest on any judgment recovered before any court authorized to enter the same within this state from the date of entering said judgment until satisfaction thereof is made either:

(a) At the rate specified in a contract or instrument in writing which provides for payment of interest at a specified rate until the obligation is paid; except that if the contract or instrument provides for a variable rate, at the rate in effect under the contract or instrument on the date judgment enters; or

(b) In all other cases where no rate is specified, at the rate of eight percent per annum compounded annually.