In this appeal, we must determine whether the workers’ compensation commissioner properly excluded three weeks of earnings from the calculation of an injured employee’s compensation rate. We conclude the commissioner did not err by excluding three weeks of low earnings and replacing them with earnings from three earlier weeks which more fairly represented the employee’s customary earnings.
I. Factual and Procedural Background.
Russell Harris (Harris) was hired by Jacobson Transportation Cоmpany (Jacobson) in April 2003 as an over-the-road truck driver. He was paid by the mile, and he was not guaranteed a minimum amount of work each week. Accordingly, the number of miles he drove each week varied depending on the assignments he received from Jacobson, but also on other factors such as traffic, speed limits, road construction, and weather. Harris’s weekly earnings during his employment were as follows: 1
04/26/2003 $ 702.08 08/23/2003 $ 958.72
05/03/2003 $ 851.20 08/30/2003 $ 667.20
05/10/2003 $ 295.84 05/17/2003 $1117.12 05/24/2003 $ 764.80 09/06/2003 09/13/2003 09/20/2003 $ 892.64 $ 247.36 $1036.48
05/31/2003 $ 833.76 06/07/2003 $ 0.00 06/14/2003 $1710.08 06/21/2003 $1068.64 09/27/2003 10/04/2003 10/11/2003 10/18/2003 $ 944.00 $ 227.52 $1223.76 0.00
06/28/2003 $ 538.24 07/05/2003 $ 542.08 07/12/2003 $ 355.68 07/19/2003 $ 698.59 07/26/2003 $ 0.00 08/02/2003 $ 806.51 10/25/2003 11/01/2003 11/08/2003 11/15/2003 11/22/2003 11/29/2003 $1183.52 $ 870.72 $1012.00 $1128.32 $ 940.16 $ 662.40
08/09/2003 $ 708.48 08/16/2003 $ 875.52 12/06/2003 $ 453.92
On December 9, 2003, while unloading freight in California, Harris injured his low back. The injury was diagnоsed as a lum-bosacral and thoracic spine strain, and Harris was restricted to light-duty work by a physician. Harris received a series of spinal injections after returning to work, but in March 2004 he was unable to continue driving because of the injury.
From June 2004 through September 2005, Harris sought treatment from several different doctors. Their diagnoses were generally similar, although they disagreed about the best course of treatment and whether Harris had reached maximum medical improvement. Each of the doсtors believed Harris was capable of light-duty work and recommended that he not return to truck driving.
In March 2005, Harris filed a claim for workers’ compensation benefits. After an arbitration hearing on November 8, 2005, a deputy workers’ compensation commissioner determined that Harris was permanently and totally disabled. The deputy commissioner calculated Harris’s average weekly rate pursuant to Iowa Code section 85.36(6) (2003) by using the thirteen weeks immediately prior to his injury, although Harris had argued that his earnings in several of those weeks were nonrepresen-tative and should be excluded. The deputy found Harris’s average weekly earnings were $827.52 and his weekly compensation rate was $483.99. 2
*195 Both parties appealed, Jacobson 3 contending the deputy erred in concluding Harris was permanently and totally disabled and Harris contending the deputy calculated the average weekly rate incorrectly. In the appeal decision, the workers’ compensation commissioner agreed with the deputy commissioner’s finding thаt Harris is totally disabled. However, the commissioner concluded three of the thirteen weeks preceding Harris’s injury were not representative 4 and should have been excluded from the calculation of Harris’s average weekly earnings. Accordingly, the commissioner calculated Harris’s average weekly earnings at $953.50 and his weekly compensation rate at $545.51. 5
When calculating Harris’s weekly compensation rate, the commissioner cited
Hanigan v. Hedstrom Concrete Products, Inc.,
The weekly earnings range from a high of $1,223.76 to a low of $227.52. When reviewing the distribution of. earnings I find that there are five weeks in which claimant earned $1,012.00 or more per week. There were two weeks in which claimant earned $247.36 per week or less. Over the 30 weekly pay periods that claimant worked for the employеr his total earnings were $24,317.34-The weekly average of claimant’s total earnings is thus $810.58. For the thirteen weeks immediately prior to his work injury, claimant earned more than $810.58 in ten of those weeks. 6 It is concluded that claimant’s average weekly wage should be calculated by discarding the weeks ending December 6, 2003 ($453.92), October 4, 2003 ($227.52), and September 13, 2003 ($247.36). By discarding those three weeks and adding earnings for the weeks ending August 30, 2003 ($667.20), August 23, 2003 ($958.72), and August 16, 2003 ($875.52) it is concluded that claimant’s gross earnings for the period are $12,395.44. When divided by thirteen weeks the average weekly gross earnings are $953.50.
*196 Jacobson sought judicial review, contending the commissioner erred both in determining Harris was permanently and totally disabled and in calculating Harris’s weekly compensation. The district court affirmed the commissioner’s decision. Jacobson appealed, and we transferred the case to the court of appeals. The court of appeals affirmed the disability decision, but reversed the commissioner’s calculation of average weekly earnings and reinstated the deputy commissioner’s lower calculation. We granted Harris’s petition for further review to address the earnings issue.
II. Scope of Review.
Our review of a decision of the workers’ compensation commissioner varies depending on the type of error allegedly committed by the commissioner. If the error is one of fact, we must determine if the commissioner’s findings are supported by substantial evidence. Iowa Code § 17A.19(10)CO;
Meyer v. IBP, Inc.,
In this case, the commissioner concluded three of the thirteen weeks prior to Harris’s injury did not fairly reflect his customary earnings and replaced them with weeks that he concluded did represent Harris’s customary earnings. There is no factual dispute concerning the amount of Harris’s wages in the weeks prior to the injury. The dispute centers instead on the commissioner’s interpretation of the words “customary earnings” in Iowa Code section 85.36(6) and his application of the law to the facts. Accordingly, we must first determine whether the commissioner has misinterpreted the law. Iowa Code § 17A.19(10)(e);
Meyer,
III. Discussion.
Iowa Code section 85.36 describes the basis for calculating a disabled employee’s compensation rate. “The basis оf compensation shall be the weekly earnings of the injured employee at the time of the injury.” Iowa Code § 85.36.
In the case of an employee who is paid on a daily or hourly basis, or by the output of the employee, the weekly earnings shall be computed by dividing by thirteen the earnings, not including overtime or premium pay, of the employee earned in the employ of the employer in the last completed period of thirteen consecutive calendar weeks immediаtely preceding the injury. If the employee was absent from employment for reasons personal to the employee during part of the thirteen calendar weeks preceding the injury, the employee’s weekly earnings shall be the amount the employee would have earned had the employee worked when work was available to other employees of the employer in a similar occupation. A week which *197 does not fairly reflect the employee’s customаry earnings shall he replaced by the closest previous week with earnings that fairly represent the employee’s customary earnings.
Id. § 85.36(6) (emphasis added). 7
Jacobson alleges the commissioner misinterpreted the last sentence of this provision authorizing the replacement of weeks which do not reflect the employee’s “customary earnings.” Because Harris’s weekly earnings fluctuated based on the number of miles he drove and because Harris was not guaranteed a uniform number of miles each week, Jacobson posits that the only customary feature of Harris’s earnings is their variability. Accordingly, in the case of an employee like Harris, Jacobson argues, the statute does not authorize the commissioner to exclude weekly earnings simply because they are significantly lower than other weeks without an explanation for the low wages that provides a rationale beyond the expected fluctuation in miles occurring from week to week.
Our goal, when interрreting a statute, is to give effect to the intent of the legislature.
Griffin Pipe Prods. Co. v. Guarino,
Consistent with the remedial nature of workers’ compensation laws, statutes for computation of wage bases are “meant to be applied, not mechanically nor technically, but flexibly, with a view always to achieving the ultimate objective of reflecting fairly the claimant’s probable future earning loss.”
Hanigan,
We think our decision in
Griffin Pipe,
interpreting section 85.36(6), informs our analysis here. In that case, Guarino was an hourly-paid employee at the Griffin Pipe plant.
See Griffin Pipe,
*198 In our review, we agreed with the commissioner’s decision to replace the weeks when the plant was closed. Although the closing of the plant was planned and routine, we explicitly rejected any distinction between anticipated and unanticipated occurrences causing a reduction in an employee’s wages.
Why a particular week may not reflect the employee’s customary hours is important only insofar as it might be relevant to whether the hours worked in that week are in fact customary....
We agree with the agency that the issue under section 85.36 “is whether the hours of work in any particular workweek are representative of the hours typically or customarily worked by an employee during a typical or customary full week of work.”
Id. at 866.
Although not in effect at the time of Guarino’s injury, we also discussed the 2000 amendment to section 85.36(6) which added to the statute the language at issue in this case.
Griffin Pipe,
confirmed this court’s interpretation of section 85.36.... Accordingly, to determine what weeks should be included in the compensation rate calculation one must ask whether the earnings attributable to a particular week are customary, not whether a particular absence from work is anticipated.
Griffin Pipe,
Thus, in our interpretation of section 85.36, both before and after the addition of the language at issue in this case, we have determined that one must look to the earnings themselves to see if they are customary. The reason for the variance in earnings is not determinative of whether a week’s earnings should be replaced because they are not customary. 9
Next, then, we must address whether an employee whose earnings fluctuate eaсh week can ever have atypical weekly earnings justifying replacement under section 85.36(6). Jacobson argues that because Harris’s miles were not fixed or uniform each week, Harris’s weekly earnings should have been calculated using the thirteen most recent weeks of earnings, without regard to the amount of his average earnings. 10 In effect, Jacobson advocates for a bright-line rule that would pre- *199 elude the replacement of a week’s earnings under section 85.36 if the emрloyee’s earnings customarily vary from week to week.
We do not interpret the word “customary” so rigidly as to conclude that just because an employee’s schedule or output is neither fixed nor guaranteed, the employee cannot have “customary” earnings. “Customary” means “based on or established by custom”; “commonly practiced, used or observed”; or “usual.”
Merriam-Webster’s Collegiate Dictionary
285 (10th ed.2002). We have previously defined “customary” as “typical.”
Griffin Pipe,
We believe the commissioner’s interpretation of “customary earnings” is compatible with the legislature’s directive that injured employees’ weekly rate of compensation shall be based on their “average spendablе weekly earnings” at the time of the injury. Iowa Code § 85.34(2), (3) (emphasis added). The legislature’s adoption of the concept of earnings-averaging as a first principle of rate calculation evidences an intention to base workers’ compensation rates on an earnings history of several weeks that are more likely than earnings of a single week to fairly represent the claimant’s probable future earning loss. The legislature’s intent to provide even greater protection to injured workers with variable earnings from the harsh effects of basing the weekly rate of compensation on unusually low-pay weeks is clearly evidenced by the amendment to section 85.36(6) adopted in 2000. As amended, the section expressly authorizes the commissioner to exclude from the computation of average weekly earnings weeks in which injured employees’ earnings do not fairly represent their customary earnings.
Our interpretation of “customary earnings” is further supported by the fact that all calculations of Harris’s average weekly earnings, whether performed by either of the parties or by the agency, have replaced the October 18 week of zero earnings with an earlier week in which Harris had earnings. Although no explanation has been provided for this replacement, we think it demonstrates a common sense understanding of what is considered customary. Even for an employee like Harris whose earnings vary each week, a wеek of zero earnings is not customary. This raises the question: If a week of zero earnings is so low that it must be excluded as not typical, where should the line be drawn? What of a week of $100 earnings? Because we think the determination of what *200 earnings are customary will depend on the specific facts of each case, we reject a bright-line rule that any employee whose wages vary may not have weeks excluded as noncustomary. Instead, we think the determination of whether wages are customary under the circumstances is a matter expressly committed by section 85.36(6) to the discretion of the commissioner. Accordingly, we conclude the commissioner correctly interpreted section 85.36(6).
We must next decide whether the commissioner’s decision to replace the three weeks of Harris’s earnings was illogical, irrational, or wholly unjustifiable in this case. The commissioner’s appeal decision discloses a careful and thorough consideration of Harris’s earnings during each of the thirteen weeks immediately prior to the injury and a thoughtful comparison of how the earnings in those weeks compared with those paid to Harris during earlier weeks of employment with Jacobson. After reviewing the weekly earnings and comparing them to the average weekly earnings for Harris’s prior career as an employee of Jacobson, the commissioner concluded the earnings from three of the weeks were so low as to be not customary and replaced them with the immediately preceding three weeks of earnings. In deciding whether Harris’s earnings during the three disputed weeks were so substantially lower than what he usually earned as to be unrepresentative, we conclude the commissioner aptly compared the earnings from those weeks with Harris’s broader earnings history. When viewed in this way, the three weeks excluded by the commissioner were so far afield from Harris’s usual earnings as to be fairly characterized as unrepresentative of customary earnings.
While we do not believe the analysis undertaken by the commissioner in this case is the only appropriate method of arriving at a determination of whether earnings are customary, we conclude it was reasonable under the circumstances presented here.
Jacobson contends that even if the commissioner did not err in excluding the three lowest weeks of earnings, it was irrational and arbitrary to exclude only the lowest weeks and not the highest weeks.
11
As we have already noted, workers’ compensation statutes are to be interpreted and applied liberally and flexibly for the benefit of the worker.
Griffin Pipe,
IV. Conclusion.
We agree with the workers’ compensation commissioner’s interpretation of section 85.36(6). His decision to replace three low weeks of earnings with weeks in whiсh Harris’s weekly earnings fairly represented customary earnings was not irrational, illogical, or wholly unjustifiable.
DECISION OF COURT OF APPEALS VACATED; DISTRICT COURT JUDGMENT AFFIRMED.
Notes
. This list of Harris's weekly earnings includes only his earnings up to the date of his injury, although he continued to work for Jacobson for several months after being injured.
. The deputy commissioner apparently excluded the week ending October 18, 2003, in which Harris had zero earnings and replaced it with the week ending September 6, 2003, in which Harris earned $892.64. The exclusion *195 of that week from the calculation of Harris’s wage rate has not been challenged in this case.
. Jacobson and its insurance carrier, Liberty Mutual Insurance, were codefendants before the agency and are copetitioners on judicial review. We refer to them jointly as “Jacobson” in this opinion.
. As in the deputy’s arbitration award, the commissioner’s appeal decision also did not include in the rate calculation the week of October 18 in which Harris had no earnings. Although there is some evidence in the record tеnding to prove Harris missed work in October because he was hunting, had the agency concluded Harris's lack of earnings were due to personal reasons, section 85.36(6) provides the weekly earnings for such period “shall be the amount [Harris] would have earned had [he] worked when work was available to other employees of [Jacobson] in a similar occupation.” Iowa Code § 85.36(6). Neither the arbitration decision nor the appeal decision explains the exclusion of the October 18 earnings. As neither party challenges the commissioner’s exclusion of the week of October 18 from consideration in the calculation of the weekly rate, we assume without deciding for purposes of our opinion that the exclusion was appropriate.
. Although the commissioner's appeal decision found Harris’s weekly compensation rate was $549.90, an order nunc pro tunc was later entered conforming the rate to the applicable rate table.
. Although the commissioner states that ten of the thirteen weeks of earnings exceeded $810.58, our review of the earnings history indicates that Harris earned more than $810.58 in nine of the weeks.
. The last two sentences, including the one at issue in this case, were added to the statute in 2000. 2000 Iowa Acts ch. 1007, § 2.
. Guarino's injury occurred before section 85.36(6) was amended adding the sentence explicitly requiring the replacement of weeks of earnings that do not fairly reflect the employee’s customаry earnings. However, as discussed, our interpretation of section 85.36(6) both before and after the amendment is relevant in this case.
. The reason for nontypical wages is relevant if the employee was absent from work for reasons personal to the employee. As previously noted, section 85.36(6) provides for a different method of addressing a nontypical week of earnings due to personal reasons. In that case, the weekly wages must be replaced with the wages thе employee "would have earned had the employee worked when work was available” to the employer’s workers performing in a similar occupation. Iowa Code § 85.36(6).
. Again, Jacobson does not argue that the week ending October 18 with zero earnings should be included in the calculation.
. It should be noted at this juncture that the legislature has provided protection to the employer from the risk of rate calculations based on weeks of unusually high earnings by excluding overtime and premium pay from average weekly wage computations. Iowa Code § 85.36(6).