Generation X is the undersize cohort of people wedged between far bigger generations: their boomer elders and their millennial successors.

Nevertheless, they have disproportionately more investable assets ($7.2 trillion) than any other age cohort. They're also considered more reticent and self-reliant than the gregarious baby boom generation that preceded them, which may explain why many financial advisers have overlooked the opportunity to serve this wealthy class of investors.

This is one of several conclusions from a recent survey by Weber Shandwick. The study indicates that not a single financial services company that segments its websites by generation (about half of those examined) focused on Generation X. Yet the study also finds that this generation of 60 million people, compared to 67.9 million millennials (which were defined as people born between 1981 and 1996; the U.S. Census Bureau, which defines millennials as those born between 1982 and 2000, counted 83.1 million as of June 2015) and 74.9 million baby boomers, is increasingly worried about financial security, particularly in the aftermath of the Great Recession.