(concurring in part and dissenting in part).
[¶ 29.] I agree with the majority’s analysis on Issue 1, but I would affirm the trial court on Issue 2, as I believe the majority retroactively applies SDCL 25-7-6.18, enacted July 1, 1997, to child care expenses paid in 1996. Under this new statute, those expenses are now allocated between the parents similar to apportionment of medical and dental insurance costs. Cf. SDCL 25-7-6.16. Thus, like insurance payments, overpayment by one parent might be reimbursable. Before July 1997, however, child care expenses were simply part of the computation of child support. See SDCL 25-7-6.10(6) (Michie 1992)(amended 1997). Under this former statute, child care expenses were denominated as a deviation factor in computing child support from the schedule in SDCL 25-7-6.2. The deviation was not a separate amount, as the majority suggests, but merely an adjustment to the amount provided in the support schedule. The former statute no more allowed payors *453reimbursement for overpayment than it allowed payees reimbursement for underpayment. Such payments were all designated as child support and, as we all acknowledge, cannot be retroactively modified. SDCL 25-7-7.3.
[¶ 30.] SABERS, Justice, joins this writing.