Hidemaru Yamaguchi Citi The buy side says: “Overall great client service — notes that are timely and thoughtful, and insightful voice mail messages.”

It’s a solid decade in first place for Hidemaru ­Yamaguchi. The Citi analyst, 45, is appreciated for the quality of his research: “He compiles his own earnings models, rather than letting young research associates take care of them, which shows his in-depth understanding of the companies’ profit structures,” cheers one aficionado. Adds another: “It is helpful that his research focuses on stock picking, as opposed to scientific research into the pharmaceuticals sector.” In August, ­Yamaguchi upgraded medical supplier Terumo Corp. from hold to buy, at ¥4,160, largely on the rapid growth of the Tokyo-­based outfit’s overseas catheter sales. A month later the shares reached ¥4,575 and he downgraded them to hold, on valuation, seizing a 10 percent run-up; during that period the sector advanced just 4.7 percent. By the end of February, Terumo shares had slipped to ¥4,470, a loss of 2.3 percent that trailed the sector by 2.7 percentage points. ­Yamaguchi “is a good source with which we can evaluate the potential of the pipeline at each drug company,” explains one portfolio manager.

Polling and tabulation of data as well as reporting on the sector profiles were completed before the March 11 Tohoku earthquake.