Every rebuttable presumption is either:
(1) A presumption affecting the burden of producing evidence and requiring the trier of fact to assume the existence of the presumed fact, unless credible evidence sufficient to sustain a finding of the nonexistence of the presumed fact is introduced, in which event, the existence or nonexistence of the presumed fact shall be determined from the evidence without regard to the presumption; or
(2) A presumption affecting the burden of proof that imposes upon the party against whom it operates the burden of proof concerning the nonexistence of the presumed fact.