The world’s non-wealthy households haven’t done so well over the last half-dozen years, says a new report released last week by a major global business consulting company.

From 2001 through 2006, reports the Boston Consulting Group, the non-wealthy of the world — those households holding less than $100,000 in financial assets — saw the total value of their assets slightly decline.

Over those same years, the consulting group’s new Global Wealth 2007 documents, total world wealth actually increased, up a brisk 7.5 percent just last year alone

So where did all that new wealth end up? At the top. So far this century, the 16.5 percent of global households with at least $100,000 to invest have seen their assets soar 64 percent in value, to $84.5 trillion.

A huge chunk of that wealth has settled in the portfolios of millionaire households, those families with at least $1 million in “assets under management” — a wealth scorecard calculation that excludes personal residences as well as jewelry, artwork, and other luxury collectibles.

These millionaire households, just 0.7 percent of the globe’s total households, now hold over a third of the world’s wealth. Where will you find these millionaire households? Nearly half hail from North America, with about a quarter from Europe.

The data for the new Boston Consulting Group report come from 62 countries that represent over 96 percent of global GDP. The authors also surveyed 111 wealth managers, who together oversee client accounts worth $9.9 trillion.

The newly released Boston Consulting Group figures match up fairly consistently with global wealth stats released this past June by researchers with Merrill Lynch and Capgemini. That study counted, world-wide, 9.5 million “high net worth individuals” with over $1 million in financial assets.

The Boston Consulting Group, using a different survey methodology, places the global millionaire total at 9.6 million.

Managing the assets of these wealthy, the new Boston Consulting Group report finds, can be an enormously lucrative line of work. The 111 wealth managers BCG surveyed boasted an astounding “median pretax profit margin” of 34.7 percent.