The trial court erred in determining the existence of a “substantial change in circumstances” based on the termination of alimony and automobile payments as contemplated by the divorce judgment.  In re Hughes
 There was no substantial change in circumstances so as to justify a downward modification of a father’s child support obligation, notwithstanding the father’s argument that his payment of college expenses created such a substantial change in circumstances, where the parties’ agreement provided for this very occurrence and, in addition, the father’s income had actually increased since the last modification of judgment.  Mulry v. Mulry
 An increase in father’s net income due to his ability to deduct maintenance payments does not constitute a substantial change in circumstances.  Pylawka v. Pylawka

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