Citicorp Earnings Soar: The nation's largest bank reported sharply higher profits for the fourth quarter and all of 1994. New York-based Citicorp said net income in the quarter rose 81% to $1.04 billion, or $2.20 a share, from $575 million, or $1.16 a share, a year earlier. For the full year, its net income rose to $3.37 billion, or $7.03 a share, from $2.22 billion, or $4.50 a share. The bank said its commercial and consumer credit costs fell sharply and that it benefited from a lower effective tax rate. Analysts said its basic businesses turned in solid quarterly and annual performances. Even so, Citicorp's stock fell $1.375 to $39 on the NYSE. Raphael Soifer of Brown Bros. Harriman said the drop reflects worries about the impact of Mexico's financial crisis.