Amestoy, C.J.
Father appeals from a family court order that upheld the magistrate’s determination of his child support obligation. He claims that there has been no change in circumstances as required by 15 V.S.A. § 660(a) prior to modifying a child support order. He also argues that the magistrate abused her discretion by (1) establishing child support under 15 V.S.A. § 656(d) (where combined available income exceeds guidelines) without extrapolating from the guidelines, (2) ordering child support that exceeds the stated needs of the children, and (3) awarding arrearages. Further, he maintains that the magistrate had no jurisdiction to award attorney’s fees. Mother cross-appeals, claiming that the magistrate abused her discretion by denying mother post-evidentiary-hearing attorney’s fees when she awarded all other legal fees. We affirm in all respects.
The parties divorced in 1988. The final divorce order granted mother sole physical parental rights and responsibilities of the parties’ three minor children and ordered father to pay $1,378.61 per month to mother in child support for the first year. The child support obligation was calculated under the child support guidelines and was to be recalculated in 1989, 1990 and every two years thereafter. The order specified the method to compute child support in the future, including when the parties’ combined monthly gross income exceeds the incomes in the child support guidelines. The final order also provided that all disputes arising under any of its provisions would be resolved by alternative-dispute-resolution procedures detailed in the order.
In 1990, the parties submitted the matter of child support to an arbitrator who calculated father’s monthly obligation to be $1,984.44 under the 1990 amended child support guidelines. The arbitrator also modified the final divorce order by detailing new procedures for determining future child support obligations under the 1990 guidelines and when the parties’ combined available income exceeds the guidelines. After 1990, the parties never agreed on the child support obligation and never had the dispute resolved again by arbitration. In 1994, mother moved in family court to modify child support.
In February 1995, the family court concluded that there had been substantial and unanticipated material changes in circumstances since the final divorce order in 1988. The court found that the alternative-dispute-resolution provision of the final order did not work for recalculating child support because the parties were unable [16]*16to cooperate and father had not acted in good faith under the provision. The court further found an unanticipated change in circumstances in the creation of the family court and the office of the magistrate, which was specifically designed to determine child support issues. Accordingly, the court modified the 1988 final divorce order by ordering that disputes regarding child support be submitted to the magistrate rather than be subject to the alternative-dispute-resolution provision of the final order. The court concluded that it was in the children’s best interest for support to be reviewed and, if necessary, recalculated pursuant to applicable statutes.
Following an evidentiary hearing, the magistrate issued oral findings and conclusions of law on October 4, 1995, which we briefly summarize. Father, who is a physician, earned $189,367 from employment in 1994, and mother, who is a teacher, earned $20,164.89. Father paid mother $6,000 per year in spousal maintenance and $20,549.16 (12 x $1,712.43) per year in child support. The magistrate concluded that mother was unable to support the children at the standard of living the children would have enjoyed had the parties remained together. See 15 V.S.A. §§ 650,654 (child support should approximate standard of living children would enjoy if parents lived together). Further, the magistrate determined that she should set the child support under 15 V.S.A. § 656(d) (use of discretion) because she believed that the parties’ combined monthly available income exceeded the uppermost level of the guidelines.
On November 16,1995, the magistrate issued an order establishing child support from the date of mother’s motion to modify in February 1994 until the parties’ eldest child reached age eighteen in June 1994 at $3,682.15 per month (24% of father’s gross income). From June 1994 until August 1996, when the second child reached age eighteen, the order set child support at $3,221.88 per month (21% of father’s gross income). From August 1996 until the youngest child reaches age eighteen, the order set child support at 18% of father’s gross income. She concluded that this system of determining child support will ensure that the custodial parent has adequate funds to support the children in a lifestyle that they should enjoy year-round, not simply during visitation with their father. The magistrate also calculated arrearages and ordered father to pay mother’s attorney’s fees of $4,521.60.
Father appealed to the family court, which affirmed the decision of the magistrate. He now appeals from the decision of the family court. Mother cross-appeals the magistrate’s decision to award her less than all of her attorney’s fees. ;
[17]*17I.
Father first claims that there was no showing before the magistrate of a real, substantial and unanticipated change of circumstances, necessary under 15 V.S.A. § 660(a) to modify the child support obligation. Section 660(a) states that “upon a showing of a real, substantial and unanticipated change of circumstances, the court may annul, vary or modify a child support order, whether or not the order is based upon a stipulation or agreement.” A change in circumstances is a jurisdictional prerequisite to modification of a child support order. McCormick v. McCormick, 150 Vt. 431, 436, 553 A.2d 1098, 1101 (1988).
Although father challenges the magistrate’s finding of changed circumstances, it was the family court’s prior February 1995 decision that found the jurisdictional prerequisite. The court found that the father had not acted in good faith in carrying out the provisions of the 1988 order relating to child support recalculation. We agree that father’s bad faith in failing to use the alternative-dispute-resolution procedures mandated in the 1988 order constitutes a change in circumstances sufficient to confer jurisdiction to modify the previous order. Cf. Galbis n Nadal, 626 A.2d 26, 28 (D.C. 1993) (father’s unilateral actions in disregard of court order constituted changed circumstances for purposes of modifying custody order); Babka v. Babka, 452 N.W2d 286, 290 (Neb. 1990) (petitioner’s unilateral action in claiming dependency tax exemptions contrary to parties’ prior agreement and action was material change in circumstances). Consequently, the magistrate’s finding of changed circumstances was unnecessary; this finding had already been made before remand from the family court, in a decision that father did not appeal.
The court also found that the creation of the family court and the office of the magistrate, along with the new statutory framework for calculating child support, constituted an unanticipated change in circumstances. See Schmitt v. Schmitt, 477 N.W2d 563, 566 (Neb. 1991) (adoption of child support guidelines constituted material change in circumstances sufficient to justify modification). We need not decide whether this change in circumstances also satisfies 15 V.S.A. § 660(a). One unanticipated change in circumstances is sufficient to confer jurisdiction to modify the child support order.
II.
Generally, once the jurisdictional threshold of changed circumstances has been met, the court must calculate the parties’ combined [18]*18available income. “Available income” is defined as gross income minus certain deductions; those relevant in this case would be spousal support, health insurance for the children, FICA taxes, and state and federal income taxes. See 15 V.S.A. § 653(1). The child support guidelines indicate the amount that parents living together with such a combined available income ordinarily spend on their children. See 15 V.S.A. § 654 (secretary of human services shall prescribe such guidelines); Office of Child Support, Child Support Guidelines § 1002 at 1-5 (1990) (table of intact family expenditures on children).1 The amount of child support indicated on the guideline table is presumed to be the total support obligation of the parents. See 15 V.S.A. § 654. The total support obligation is divided between the parents in proportion to their respective available incomes, and the noncustodial parent pays his or her share to the custodial parent. See id. § 656.
Under the 1990 child support guidelines, the highest combined available income covered on the table is $11,574.99 per month. Section 656(d) provides, “The court may use its discretion in determining child support in circumstances where combined available income exceeds the uppermost levels of the support guidelinefs.]” Although father argued before the magistrate and before the family court that the parties’ combined available income did not exceed the highest guideline level, he has not raised this issue before us. Here, the premise of father’s claim of error is that the parties’ available income exceeds the highest income in the guidelines.2
III.
Father’s mam argument is that the magistrate abused her discretion by failing to extrapolate from the guidelines after concluding that the parties’ available income exceeded the highest income in the guidelines.3 He relies, in part, on Smith v. Stewart, 165 Vt. 364, 684 [19]*19A.2d 265 (1996), in which we outlined the requirements for determining child support under 15 V.S A. § 656(d). In Smith, we held that, in exercising its discretion under § 656(d), the court must consider the factors specified in § 659(a) (if guideline amount is unfair, court may adjust child support amount). 165 Vt. at 372, 684 A.2d at 270. “As long as the court considers the statutory factors, makes adequate findings and explains its reasoning in determining the support obligation, its discretion is not limited to adopt or avoid a particular methodology.” Id. The only other requirement under § 656(d) is that the court’s decision must be consistent with the principles behind the guidelines. See id. Thus, we did not reject extrapolation from the guidelines, but we do not require the court to extrapolate either.
The statute does not require a particular methodology; accordingly, there was no abuse of discretion in declining to adopt the method of extrapolation. See Voishan v. Palma, 609 A.2d 319, 326 (Md. 1992) (legislature did not intend to limit judge’s discretion where income exceeds guidelines by requiring mechanical extrapolation); Nash v. Mulle, 846 S.W2d 803, 806 (Tenn. 1993) (where obligor’s income exceeds guidelines, court is not limited to applying guideline percentages but retains discretion to set obligation on case-by-case basis).
Father contends that the court should be required to extrapolate from the guidelines because child support orders would then be more consistent with the principles underlying the guidelines. The main purpose of the guidelines is to ensure that children enjoy the same standard of living they would enjoy if their parents were living [20]*20together. See 15 V.S.A. § 650 (legislative purpose is that child support should reflect standard of living child would have enjoyed if marriage had not dissolved); id. § 654 (guidelines shall be based on concept that children should receive same proportion of parental income after separation as they would if parents were living together). The Legislature also intended the guidelines to improve the efficiency of child support adjudication and to eliminate discrepancies in awards for children in similar circumstances. Smith, 165 Vt. at 367, 684 A.2d at 267. In this case, the magistrate’s order corresponds to all three purposes.
Most importantly, the magistrate found that mother was unable to support the children at the same standard of living they would have enjoyed had the family remained intact. The disparity between the children’s lifestyle in the two parties’ homes was apparent. For example, the magistrate found that father spends an average of $22 per day per child for food, whereas mother spends an average of about $9 per day per child. Had the family been living together, she found, they would be taking annual vacations, going out to eat more frequently than an average income household and enjoying a lifestyle mother was unable to afford. The magistrate explained that the new child support order provided mother with adequate resources to support the minor children in a lifestyle they should enjoy year-round, not simply during visitation with father. See Nash, 846 S.W2d at 805 (one of primary goals of guidelines is to allow child of wealthy parent to share in very high standard of living); Bagley v. Bagley, 632 A.2d 229, 239 (Md. Ct. Spec. App. 1993) (children of affluent noncustodial parent are entitled benefits of affluent standard of living).
Second, the method of calculating child support the magistrate adopted was specifically designed to improve the efficiency of child support adjudication by basing the child support obligation on father’s gross income. Father contends that the statute mandates that child support obligations be based on combined available income. Under 15 V.S.A. § 656(d), the court may use its discretion to determine child support “where combined available income exceeds the uppermost levels of the support guideline[s].” (Emphasis added.) Accordingly, the court must calculate the parties’ available income.to determine if this section applies; however, there is no statutory requirement that child support be calculated based on available income once the court determines that the available income exceeds the guidelines.
Here, the magistrate explained at length that calculating father’s available income would be difficult for the parties because father has [21]*21a combination of W-2 wage income, self-employed consulting income and income from joint spousal investments. His state tax burden in New Jersey would create additional disputes. The fact that father tried to present an expert witness on the issue of his available income only emphasizes the difficulty the parties would have in determining the future child support obligation on this basis. The magistrate concluded that basing child support on available income (1) would be contrary to the purpose of the child support guidelines in providing a predictable and easy method for parents to review child support on an annual basis, and (2) would involve the parties in year after year of litigation. Accordingly, the magistrate designed a method of calculation to prevent future litigation, which she found had been painful and expensive for the family. That litigation has not ended may demonstrate that the magistrate gave the parties too much credit for civility, but it does not demonstrate abuse of discretion.
The third purpose of the guidelines is to eliminate discrepancies between child support orders. Father argues that, without requiring extrapolation from the guideline tables, orders will be inconsistent, and similarly situated obligors will be treated differently. He claims that it is inequitable, for example, to require him to pay 21% of his gross income to support two children when the high end of the guidelines calls for 19% of the family’s combined available income.
Obviously, reducing discrepancies between child support orders is more readily achievable when the guidelines apply than when they do not. And child support orders would be more certain and consistent if the guidelines applied to more cases or if extrapolation were required. Other states have adopted statutes that give less discretion to courts, or at least provide more guidance to courts, than the Vermont statute. See, e.g., In re Marriage of Patterson, 920 P.2d 450, 457 (Kan. Ct. App. 1996) (guideline formula for extrapolation does not create rebuttable presumption but court must consider extrapolation amount in exercising discretion); Schultz v. Schultz, 675 N.E.2d 55, 59 (Ohio Ct. App. 1996) (presumption is that child support is not less than high-end guideline percentage of parents’ income); Archer v. Archer, 813 P.2d 1059, 1061 (Okla. Ct. App. 1991) (minimum child support order for high-income parents is high end of guideline); Stringer v. Brandt, 877 P.2d 100, 102 (Or. Ct. App. 1994) (guidelines set presumptive cap on child support for high-income parents).
Unlike the statutes in those states, § 656(d) provides no presumptive child support minimum, maximum, or fixed amount. Our Legislature created a system where the magistrate has greater discretion [22]*22in determining child support when the noncustodial parent is wealthy. Smith, 165 Vt. at 368-69, 684 A.2d at 268. And we have previously upheld § 656(d) child support orders that diverge completely from a guideline extrapolation where the evidence supports such an order. See, e.g., C.D. v. N.M., 160 Vt. 495, 499-501, 631 A.2d 848, 851-52 (1993) (although noncustodial parent’s income was over $90,000 per year, court ordered nominal child support because children’s income exceeded their need).
Here, even after paying maintenance and child support, father lives on more than twice as much as mother, who is responsible for supporting two children at the standard of living they would have enjoyed had the marriage not been dissolved. There is no error in ordering child support that exceeds an extrapolation from the guidelines in such circumstances, and similarly situated obligors are treated similarly. See, e.g., Voishan, 609 A.2d at 326 (awarding more than the extrapolation amount where obligor’s income was more than four times that of obligee); Ochs v. Nelson, 538 N.W.2d 527, 531 (S.D. 1995) (trial court has discretion to adjust support so that child could partake in some of father’s high standard of living while with mother); Nash, 846 S.W2d at 805 (goal that child share in parent’s higher standard of living becomes significant when one parent has vastly greater resources than other).
We conclude that the magistrate’s decision complied with all the Smith requirements. In assessing the children’s need and the parents’ ability to pay, the magistrate considered the applicable statutory factors, made adequate findings and explained her reasoning. She appropriately exercised her independent judgment pursuant to statutory authority and the guideline principles.
IV.
Father next argues that, even if the magistrate has the discretion to fashion a child support order without extrapolating from the guidelines, she abused that discretion by (a) ordering child support that exceeds the needs of the children, (b) failing to divide the child support obligation between the parties as required by 15 V.S.A. § 656(a), and (c) basing child support obligations for 1994, 1995 and part of 1996 on father’s 1994 tax return. We take each of those claimed errors in turn.
[23]*23A.
Father argues that the magistrate abused her discretion by ordering child support that exceeds the needs of the children. At the hearing, mother stated that she needed $5,409 monthly to support the two remaining minor children. The magistrate concluded that her monthly gross income was $2,189.76, leaving a difference of $3,219.24. She ordered father to pay $3,221 in support for the two children, $1.76 more than requested. Father claims that, based on mother’s expenditures at the time of the hearing, mother needed a total of only $3,989 monthly. Essentially, he argues that because the children were living on less than requested, they really only needed that lesser amount.
The fact that mother was able to meet the basic needs of the children on less support than she requested “does not mean that [the children] do not have needs that should be addressed by a further increase in child support.” Smith, 165 Vt. at 369, 684 A.2d at 268. The term “need” refers to the general standard of living of the family. See id. “Children are not expected to live at a minimal level of comfort while one or more parents enjoy a luxury lifestyle.” Id. They “are entitled to a part of the ‘fruits of one parent’s good fortune after a divorce.’” Id. (quoting In re Marriage of Nimmo, 891 P.2d 1002, 1007 (Colo. 1995)). Reasonable needs of affluent children may include items that would be frivolous for children of less-well-off parents. See id. Accordingly, we find no abuse of discretion in ordering support sufficient to meet the needs of the children as presented by the evidence as opposed to support they had been able to live on in the past. See Galbis, 626 A.2d at 31 (child’s needs should not be interpreted so narrowly as to deprive child of quality of life enjoyed by noncustodial parent); Bagley, 632 A.2d at 239 (children are entitled to every expense reasonable for a child of affluent parent).
B.
Father argues that the magistrate erred by failing to divide the child support obligation between the parents as required by 15 V.S.A. § 656(a), and by specifically excluding from consideration the first $40,000 of mother’s income. We find no error. In cases where the obligation is not established from the guideline table, there is no formula for calculating or dividing child support between the parents. See C.D., 160 Vt. at 500, 631 A.2d at 851 (considering factors and setting nominal child support).
[24]*24Here, the magistrate considered mother’s income as required, see 15 V.S.A. § 659(a)(2) (financial resources of custodial parent), and determined that the children were receiving a fair share of her income because she is the custodial parent and is maintaining a home for them. As long as mother’s income remains below $40,000, the magistrate declined to include it in the equation to determine father’s obligation. The order also excludes up to $40,000 of father’s income earned from consulting to allow him to contribute to the children’s college educations. Thus, although the equation to determine father’s obligation does not include the first $40,000 of mother’s income, this income was appropriately considered in computing the parental support obligations. See 15 V.S.A. § 656(d).
C.
Father also argues that the magistrate erred by basing the child support obligation for 1994,1995 and part of 1996 on father’s 1994 tax return. He claims that the undisputed testimony was that his 1995 salary would be less than his 1994 salary. While this testimony may have been undisputed, the magistrate clearly found it not credible as she found that father’s income would continue to grow after 1994. Consequently, the 1995 child support obligation should have been based on gross income greater than indicated on the 1994 tax return. Nonetheless, she relied on the 1994 tax return because it was the most accurate and credible evidence before her. Thus, any error that occurred was in father’s favor. Although not part of the record in this appeal, a subsequent order indicates that the magistrate’s prediction was accurate and that father’s 1995 wage income was substantially higher, not lower, than the year before.
V.
Next, father contends that the magistrate abused her discretion by ordering the new child support obligation effective from the date that mother filed the motion to modify and then awarding over $30,000 in arrearages. Modification of a child support order may take effect at any time on or after the filing date of the motion to modify at the discretion of the trial court. Towne v. Towne, 150 Vt. 286, 288, 552 A.2d 404, 405 (1988). We review this determination only for abuse of discretion. See id. Here, the magistrate considered the parties’ financial circumstances in 1994 and 1995 and the standard of living the children would have enjoyed had the parties remained together. [25]*25There was no abuse of discretion in ordering the modification to take effect as of the February 1994 filing date.
Father maintains that mother is unjustly enriched because she had not been spending this amount up to the date of the hearing. As we stated in Smith, “It would be unreasonable to expect [mother] to spend more money on the children in anticipation of its coerced receipt from [father].” 165 Vt. at 369, 684 A.2d at 269. Father also claims that the award of arrearages was an abuse of discretion because there was no way he could have predicted such a deviation from the guidelines. He cites no authority and makes no argument to support this claim; thus, we need not consider it. KPC Corp. v. Book Press, Inc., 161 Vt. 145, 152, 636 A.2d 325, 329 (1993) (Court need not consider assertion in brief that was unaccompanied by facts, law or reasoning).
VI.
Father argues that the magistrate has no statutory authority to award attorney’s fees, and that, even if authority exists, the facts in this case do not justify such an award. Neither the family court nor the office of the magistrate is explicitly authorized by rule or statute to grant attorney’s fees. Nonetheless, we have long held that trial courts may make such an award. See, e.g., Loeb v. Loeb, 120 Vt. 489, 496-97, 144 A.2d 825, 830 (1958) (although statute fails to explicitly provide for award of attorney’s fees in action to modify child support, it is understood to imply provisions necessary to effectuate its object). Absent an award of attorney’s fees, a “child might be deprived of the very protection which the statute seeks to afford her.” Id. at 497, 144 A.2d at 830.
The trial in child support proceedings is generally before the magistrate. The office of the magistrate has jurisdiction to hear and dispose of “proceedings for the establishment, modification and enforcement of child support.” 4 V.S.A. § 461(a)(1). The family court has original jurisdiction over child support issues, only upon motion, under certain limited circumstances listed in 4 V.S.A. §§ 462, 463. See also V.R.F.E 4(q) (except as provided by 4 V.S A. §§ 462,463 and V.R.F.E 4(o), “a magistrate shall hear and determine all proceedings to establish or modify child support”). The family court also hears appeals on the record from decisions of the magistrate. 4 V.S.A. § 465.
“The primary consideration in an award of attorney’s fees is the ability of the supporting party to pay and the financial needs of [26]*26the party receiving the award.” Smith, 165 Vt. at 375, 684 A.2d at 272. All of the evidence to determine the financial circumstances of the parties was before the magistrate, as it was necessary to ascertain the child support obligation. We see no reason to require the parties to repeat this trial before the family court for the purpose of awarding attorney’s fees. Cf. Ely v. Ely, 139 Vt. 238, 242, 427 A.2d 361, 364 (1981) (divorce and similar actions involving financial circumstances of the parties obviate necessity of separate hearing on issue of attorney’s fees). We therefore hold that a magistrate has the authority to award attorney’s fees.
Father next argues that the facts in this case do not justify an award of attorney’s fees, and mother cross-appeals, claiming that the magistrate abused her discretion by arbitrarily denying attorney’s fees for some of her necessary legal services. The record indicates that the magistrate properly considered mother’s need and father’s ability to pay attorney’s fees. Given that father’s income was so much greater than mother’s, we conclude that the award was within the discretion of the magistrate. We also reject mother’s contention that the magistrate erred by failing to award her all her legal fees. Mother’s income is not so minimal that she is unable to bear any of the cost.
Mother also requests attorney fees of $4,101.20 for this appeal. V.R.A.E 39(f) provides, “Claims for attorneys’ fees and other nontaxable expenses arising on an appeal shall be made by motion in the trial court pursuant to Rule 54(d)(2) of the Vermont Rules of Civil Procedure within 14 days after issuance of the mandate in accordance with Rule 41(a) of these rules.” Accordingly, we remand this issue.
Affirmedmother’s request for attorney’s fees for this appeal is remanded.