OPINION
COATS, Judge'.Dennis Richards was convicted, following a jury trial, of robbery in the first degree, AS 11.41.500(a)(1). Richards was subject to a presumptive sentence of seven years. See AS 12.55.125(e)(2). Judge Rene Gonzalez found one aggravating factor and one mitigating factor applied to the sentencing. He found that “the defendant knew the offense involved more than one victim,” AS 12.55.155(c)(9), but that the “conduct constituting the offense was among the least serious conduct included in the definition of the offense,” AS 12.55.155(d)(9). Judge Gonzalez sentenced Richards to seven years with thirty months suspended and placed Richards on probation for five years following his release from confinement. The state appeals, arguing that Judge Gonzalez erred in finding the “least serious” mitigating factor and arguing that the sentence imposed was clearly mistaken. We affirm.
At the time of the offense Richards had just turned twenty years old. His only prior offenses consist of several traffic offenses and a misdemeanor offense for eluding a police officer in 1980. This conviction was set aside after Richards completed a suspended imposition of sentence.
The current offense involved the armed robbery of a McDonald’s restaurant. The weapon that Richards used in committing the robbery was unloaded and inoperable.
Factors in mitigation and factors in aggravation must be established by clear and convincing evidence. AS 12.55.155(f). A finding by the trial court that an aggravating or mitigating factor exists is entitled to deference, and we are to reverse the trial court’s decision only if we find the decision is clearly erroneous. Juneby v. State, 641 P.2d 823, 834 (Alaska App.1982), *49modified, on other grounds, 665 P.2d 80 (Alaska App.1983). Judge Gonzalez, in finding the mitigating factor, acknowledged that this was a close case. We conclude that the fact that the weapon that was used was inoperable, and the apparent lack of planning of the robbery on Richards’ part, support Judge Gonzalez’ decision to find the mitigating factor. We also conclude that the facts of the robbery, the age of the defendant, and his lack of a prior record support the sentence which Judge Gonzalez imposed. We do not find that the sentence was clearly mistaken.
AFFIRMED.