BACKGROUND
The claimant, Jeff McClurg (“McClurg”), worked for sixteen years as a painter for Yanke Machine Shop, Inc. (“Yanke”), prior to an industrial accident on the job on June 9, 1987, in which he injured his back. Following surgery and attempts at rehabilitation, it became apparent that McClurg no longer was physically able to perform his job at Yanke. At present, McClurg works as a full-time permanent detention officer at the Ada County Juvenile Services Center (“Center”), resulting from his voluntary enrollment in an on-the-job training program.
McClurg applied for a hearing before the Commission on August 3, 1989, to determine the extent McClurg had suffered a permanent partial disability over and above his permanent physical impairment of six percent (6%) of the whole person. The matter was heard on July 2, 1990. In its *175findings of fact, conclusions of law, and order, the Commission found that McClurg had suffered permanent partial disability of thirty percent (30%) of the whole person. The Commission accordingly awarded McClurg permanent partial disability benefits based upon McClurg’s salary structure at the time of the accident. McClurg has appealed the decision to this Court. On appeal, we must address the following issues:
I. Whether the Commission considered the proper pre-injury and post-injury wage structure to determine claimant’s permanent partial disability benefits.
II. Whether the Commission erred in failing to consider wage increases implemented by Yanke during the interim between claimant’s accident and reemployment.
STANDARD OF REVIEW
This Court reviews an appeal from the Industrial Commission under a dual standard. Whereas we apply unlimited review to questions of law, we will not disturb the Commission’s factual findings if they are based on substantial competent evidence. I.C. § 72-732; Idaho Const. Art. 5, § 9; Loya v. J.R. Simplot Co., 120 Idaho 62, 813 P.2d 873 (1991); Lopez v. Amalgamated Sugar Co., 107 Idaho 590, 691 P.2d 1205 (1984). The degree of permanent disability suffered by a claimant is a factual question committed to the particular expertise of the Commission. Thom v. Callahan, 97 Idaho 151, 540 P.2d 1330 (1975). Applying this standard, we hold that the Commission based its award on substantial competent evidence, and we affirm.
I.
The primary purpose of an award of permanent partial disability benefits is to compensate a claimant for his or her loss of earning capacity or reduced ability to engage in gainful activity. I.C. § 72-425 and 72-430; Baldner v. Bennett’s, Inc., 103 Idaho 458, 649 P.2d 1214 (1982); Paulson v. Idaho Forest Indust., Inc., 99 Idaho 896, 591 P.2d 143 (1979). Idaho Code §§ 72-4251 and 72-430 2 guide the Commission’s calculation of a claimant’s permanent partial disability. Those sections provide that the computation of permanent disability must be based on a claimant’s ability to engage in “gainful activity,” not only as it is affected by the medical impairment factor, but also as it is affected by certain non-medical factors. Loya, 120 Idaho at 65, 813 P.2d at 876. The Commission apparently recognized that in this case when it concluded: “[claimant has suffered a 30% permanent partial disability when medical and non-medical factors are considered.”
The Commission cited Baldner v. Bennett’s, Inc., 103 Idaho 458, 649 P.2d 1214 (1982), to support its comparison of the claimant’s earnings before and after his industrial injury as a way of measuring his loss of ability to engage in gainful activity. McClurg argues, however, that Baldner authorized the comparison of annual earnings, and the Commission instead erroneously compared his hourly wages pre-injury and post-injury. As a matter of law, we hold that, although the Commission in Baldner utilized pre-injury and post-injury annual earnings, nothing in our decision in that case mandates that the Commission do so rather than looking to hourly wages. *176Nor is the Commission constrained to regard weekly rather than hourly wages, as claimant also contends. The only requirement is that the Commission’s comparison of pre-injury and post-injury income levels “accurately reflects [a claimant’s] ability to engage in gainful activity.” Bennett v. Clark Hereford Ranch, 106 Idaho 438, 442, 680 P.2d 539, 543 (1984).
The Commission’s findings that McClurg generally worked forty-five hours per week and was earning $11.15 per hour at the time of his injury are clearly supported in the record by substantial competent evidence. McClurg personally testified that he worked approximately forty-five hours per week during the summer and less during the winter. Yanke offered no contradictory evidence. Claimant’s uncontroverted exhibits also support these findings. The Commission’s comparison of McClurg's hourly wages in this case to assist in its determination of his lost earning capacity was entirely proper. The numbers it relied upon to represent the loss of McClurg’s earning capacity were supported by substantial competent evidence.
II.
McClurg’s claim that the Commission should have considered wage increases implemented by Yanke during the interim between his injury and subsequent employment at the Center is unsupported by law and too speculative for this Court to embrace. We cannot ascertain whether claimant would have continued working at Yanke, or whether he would have received the same raises the current employees have received. Despite the lack of legal authority in Idaho, claimant ventures into nonjurisdictional case law to reap support for his position. We find claimant’s attempts at analogy unpersuasive. This is not a case where injustice has resulted by virtue of a failure to account for intervening wage increases at McClurg’s former employment.
The Commission’s award of thirty percent (30%) permanent partial disability of the whole person is affirmed.
Costs to respondent.
BAKES, C.J., JOHNSON, J., and REINHARDT, J. Pro Tern., concur.. "Evaluation (rating) of permanent disability” is an appraisal of the injured employee's present and probable future ability to engage in gainful activity as it is affected by the medical factor of permanent impairment and by pertinent nonmedical factors provided in section 72-430, Idaho Code. I.C. § 72-425.
. Idaho Code § 72-430(1) states:
Matters to be considered. In determining percentages of permanent disabilities, account shall be taken of the nature of the physical disablement, the disfigurement if of a kind likely to handicap the employee in procuring or holding employment, the cumulative effect of multiple injuries, the occupation of the employee, and his age at the time of accident causing the injury, or manifestation of the occupational disease, consideration being given to the diminished ability of the afflicted employee to compete in an open labor market within a reasonable geographical area considering all the personal and economic circumstances of the employee, and other factors as the commission may deem relevant____