After a bench trial, a trial court must enter findings of fact and conclusions of law when requested to do so before trial. Ariz. R. Civ. P. 52(a); Miller v. McAlister, 151 Ariz. 435, 436-37, 728 P.2d 654, 655-56 (App. 1986). It is only required to make findings on the ultimate facts, not each subsidiary evidentiary fact on which the ultimate facts are based. Gilliland v. Rodriquez, 77 Ariz. 163, 167, 268 P.2d 334, 337 (1954); Ellingson v. Fuller, 20 Ariz. App. 456, 459-60, 513 P.2d 1339, 1342-43 (1973). The ultimate facts are "'the essential and determinative facts on which the conclusion was reached.'" Miller v. Pinal County Bd. of Supervisors, 175 Ariz. 296, 300, 855 P.2d 1357, 1361 (1993), quoting Star Realty Co. v. Sellers, 73 N.M. 207, 387 P.2d 319, 320 (N.M. 1963). The purpose of requiring the trial court to enter findings of fact and conclusions of law is to enable this court to examine the bases for the trial court's decision. Reed v. Reed, 154 Ariz. 101, 103, 740 P.2d 963, 965 (App. 1987); Ellingson, 20 Ariz. App. at 460, 513 P.2d at 1343.