William Brewer, as Trustee for the heirs and next of kin of Angela Josephine Brewer, Appellant, vs. Columbia Park Medical Group, P.A., et al., Respondents.

may not be cited except as provided by

Minn. Stat. § 480 A. 08, subd. 3 (1996).

 STATE OF MINNESOTA

 IN COURT OF APPEALS

 C9-98-1389

In Re the Marriage of:

Jeffrey Brian Dugger, petitioner,

Appellant,

vs.

Suzanne Mary Freedy,

Respondent.

 Filed December 29, 1998

 Affirmed

Klaphake, Judge

Ramsey County District Court

File No. F878529138

Jeffrey Brian Dugger, P.O. Box 11704, St. Paul, MN 55111-0704 (appellant pro se)

Susan Gaertner, Ramsey County Attorney, Patricia Frank, Assistant County Attorney, 50 West Kellogg Blvd., Ste. 560, St. Paul, MN 55102 (for respondent)

Considered and decided by Peterson, Presiding Judge, Klaphake, Judge, and Anderson, Judge.

 U N P U B L I S H E D O P I N I O N

 KLAPHAKE, Judge

After the parties' child, who had been living with respondent Suzanne Freedy, was emancipated, pro se appellant Jeffrey Dugger sought review of his support obligation and the termination of income withholding. The administrative law judge (ALJ) set appellant's arrears and refused to terminate withholding. On the limited record presented to this court, we affirm the ALJ's decision.

 D E C I S I O N

Child support may be modified if the moving party shows a substantial change in circumstances rendering the existing award unreasonable and unfair. Minn. Stat. § 518.64, subd. 2(a) (Supp. 1997). Whether to modify support is discretionary with the district court and its decision will not be altered unless it abuses that discretion. Moylan v. Moylan, 384 N.W.2d 859, 864 (Minn. 1986). This standard applies to support rulings made by an ALJ. Lee v. Lee, 459 N.W.2d 365, 368-69 (Minn. App. 1990), review denied (Minn. Oct. 18, 1990). Also, because appellant did not provide a transcript, our review is limited to whether the ALJ made legal errors; we cannot review appellant's fact-based allegations of error. Cronin v. Cronin, 372 N.W.2d 778, 781 (Minn. App. 1985), review denied (Minn. Oct. 11, 1985).

Appellant argues respondent failed to follow the proper procedure for obtaining an arrears judgment. Because respondent assigned her support rights to the county, any errors on her part do not preclude the county from recovering. Also, the emancipation of the parties' child does not preclude recovery, whether by wage withholding or otherwise. See Minn. Stat. § 518.6195 (a), (b) (Supp. 1997) (if support arrears accrue before child is emancipated, methods for collecting and enforcing support continue to apply after emancipation). The county appeared at the hearing and its presence was sufficient to allow the ALJ to address appellant's requests for relief. Therefore, respondent's failure to appear at the hearing does not entitle appellant to prevail by default.

Noting respondent was on and off public assistance at various times after April 1991, appellant alleges he does not owe the county for assistance furnished after April 1991 because neither respondent nor the county obtained an order for continuing contribution under Minn. Stat. § 256.87, subd. 1a (1996). By 1991, however, an order formally reinstating a previous order for contribution was no longer required. See Minn. Stat. § 256.87, subd. 1a (1990) (if person starts receiving public assistance after prior termination thereof, prior order for contribution reinstated without hearing, upon notice to obligor).

Because the ALJ's order states she reviewed the file when making her decision, we reject appellant's claim that the ALJ did not consider his submissions. See Loth v. Loth, 227 Minn. 387, 392, 35 N.W.2d 542, 546 (1949) (appellate courts cannot assume error).[1] Also, because county child support officers are charged with maintaining support records and because the ALJ accepted the information in appellant's file after the county audited that file, we reject appellant's claim that the information in his file was unreliable after the audit. See Minn. R. Evid. 803(8) (absent indicia of untrustworthiness, data compiled by public office generally admissible); Sefkow v. Sefkow, 427 N.W.2d 203, 210 (Minn. 1988) (appellate courts defer to fact finder's credibility determinations).

Appellant claims he should not have arrears for September 1983 through July 1984 because he was on public assistance at that time. In setting arrears, the ALJ determined appellant's support obligation was suspended effective April 1, 1983, but that appellant stipulated to pay support as of October 15, 1983. We see no error by the ALJ.

We decline to address any challenges appellant makes to the judgment dissolving his second marriage. See Dieseth v. Calder Mfg. Co., 275 Minn. 365, 370, 147 N.W.2d 100, 103 (1966) (after appeal deadline expires, decision is final, even if incorrect).

Appellant argues the county cannot collect arrears more than two or ten years old. See Minn. Stat. § 256.87, subd. 1 (Supp. 1997) (distinguishing between two and ten-year recovery periods). Unpaid child support automatically becomes a judgment on the date payment is due. Minn. Stat. §§ 256.87, subd. 6 (1996); 548.091, subd. 1a (Supp. 1997). Under Minn. Stat. § 548.091, subd. 3a (Supp. 1997), a judgment continues for ten years after docketing. Because appellant does not identify when any judgment was docketed against him, we do not address this issue.

Affirmed.

[1] To the extent appellant presents evidence to this court that was not before the ALJ, we do not consider it. See Minn. R. Civ. App. P. 110.01 (defining record on appeal as items presented to district court); Mitterhauser v. Mitterhauser, 399 N.W.2d 664, 667 (Minn. App. 1987) (requiring matters outside record be stricken).