See nota 55
The following principles govern the admission of fresh evidence before an appellate court:
(i) the evidence should generally not be admitted if by due diligence it could have been adduced at trial;
(ii) the evidence must be relevant in the sense that it bears upon a decisive or potentially decisive issue at the trial;
(iii) the evidence must be credible in the sense that it was reasonably capable of belief; and
(iv) the evidence must be such that if believed, it could reasonably be expected to have affected the result at trial.
However, an appellate court may take account of a change of circumstances since the making of the order where a failure to do so would result in long-term injustice56or in an order that would necessitate variation on a fresh application.57Evidence of a loss of employment after the delivery of the trial judgment may be admitted on appeal and the amount of child support may be varied by the appellate court to reflect these changed circumstances.58
In the absence of an application to admit new evidence by way of affidavit on an appeal, the submissions of counsel are insufficient to establish a material change of circumstances.59The tender of computer-generated tables, which are merely mathematical tools enabling the court to undertake complicated calculations, does not offend the "fresh evidence" rule that customarily applies to appeals.60A judge is not functus officio where a formal order reflecting her reasons for judgment has not been entered. Where the Crown seeks reconsideration of a prior judicial remission of arrears based on the finding that the husband was unaware of his wife’s receipt of social assistance, the Crown is not ex-
empted from meeting the requirements of the "fresh evidence rule" simply because the court could have unilaterally relied upon the Provincial Court order on file to which neither party made reference in the original application. The fresh evidence rule is not rendered inapplicable because previously untendered evidence was available on the court file.61
 See, generally, Julien D Payne, Payne on Divorce, 4th ed (Scarborough, ON: Carswell, 1996) at 495-97.
 Jens v Jens, 2008 BCAC 392.
 LeBlanc v LeBlanc (1993), 48 RFL (3d) 457 (Man CA); Williams v Williams,  NJ No 254 (CA).
 Forbes v Forbes (1997), 33 RFL (4th) 251 (BCCA).
 Giles v Villeneuve,  OJ No 4492 (Gen Div).
 Meuser v Meuser,  BCJ No 2808 (CA).