It is imputed interest expense on a loan from a shareholder.  I entered it as an M-1 timing difference because I didn't find a way to input it as a permanent difference.  After asking the question, I saw I neglected to also increase interest expense by the same amount.  Increasing interest expense fixed the retained earnings issue, except that I had to override to make it a AAA item instead of a timing difference on the Schedule M-2/Retained Earnings Worksheet.