The nation's grantmaking foundations can be perceived in a multitude of ways. At the extremes, some may characterize foundations as consisting primarily of the best-known multimillion or billion-dollar institutions. Others may view them as principally consisting of "mom and pop funders" or "checkbook philanthropies," with giving decisions made around the kitchen table. In reality, U.S. private and community foundations consist of a vast array of institutional types, and the level of their giving is determined by a variety of factors. In a year when many large, endowed foundations may see their assets rise only modestly due to mixed investment performance, some smaller foundations may experience an exponential increase resulting from the sale of a family business, a bequest, or simply the decision of founders to move large shares of their wealth into the foundations. Conversely, large or small foundations heavily invested in a single stock may suffer a severe drop in their assets in a single year. Or donors may decide to make radically large gifts or to spend out their assets.