SLM 17.60, -1.49, -7.8%) reported second-quarter core earnings of $156 million, or 27 cents a share, compared with $189 million, or 43 cents a share, in the year-ago period. Analysts surveyed by FactSet Research were expecting Sallie Mae to earn 40 cents a share in the quarter on a core basis, which excludes the effect of accounting for derivatives.