Goldman Sachs is back, baby! Or at least that’s the conclusion of Mike Mayo, the influential Wall Street analyst at Wells Fargo, and it’s hard to disagree. Twenty-five years after the firm’s May 1999 I.P.O., Goldman’s stock is trading at or near its all-time high, and has a market value of almost $150 billion, narrowing the once-yawning valuation gap with rival Morgan Stanley to around $10 billion. Goldman’s first-quarter performance delighted Mayo and other Wall Street research analysts, and the outlook for the rest of the year seems bright, given the pickup in the financing and M&A markets. “They’re crushing it in their legacy business, global banking and markets, and that’s two-thirds of the company,” Mayo told me. “And the other one-third of the company, which is wealth and asset management, is on its way toward a mid-teens return.”