The Impact of Diversification on Bank Holding Company Performance

Bank holding companies (BHCs) are hypothesized to achieve potential portfolio and synergistic benefits through various forms of diversification. On the other hand, diversification can generate new managerial problems or agency costs. This dissertation examines five issues. 1) Do all the various forms of diversification have the same favorable/unfavorable effects on BHCs\u27 performance?, 2) Are there any interaction effects among the various types of diversification?, 3) Since the business strategies of large BHCs are different from those of small BHCs, do the diversification effects vary by size?, 4) How did diversification impact BHC performance during the 2007-2008 financial crisis?, and 5) What types of diversification-associated Merger and Acquisitio should BHCs employ to take advantages of diversification benefits? Overall Results - The study finds that not all forms of diversifications have the same impacts on BHCs\u27 performance. Some types of diversification support the hypothesis of favorable portfolio benefits and cost synergies, while other findings support the hypothesis of unfavorable agency costs. Non-interest-income diversification has the strongest favorable impacts on BHCs\u27 performance as it both increases returns and reduces portfolio risk. Security diversification has unfavorable impacts on accounting returns but favorable impacts on market returns. Off-balance-sheet diversification has unfavorable impacts on risk and it does not contribute to BHCs\u27 returns. The largest unfavorable impact is on derivatives losses. Moreover, for some diversification measures, the impacts depend on the scale of their associated activities. When the scale of the diversified activity is large enough, the net diversification impact may change its sign. In general, among the various diversified activities where the sign of the impacts switch with scales, loan diversification switches direction from favorable to unfavorable. BHCs might tend to make increasingly risky loans when their scale of loans expands. Moreover, ag