Most Americans with $1 million or more in assets made their money on their own, according to a study by BMO Private Bank released today.

Sixty-seven percent of high-net-worth Americans are self-made millionaires, according to the survey. Only 8 percent inherited their wealth. One third of the millionaires surveyed were women and half of them made their own fortunes.

The report by the Chicago-based bank was based on a survey of 482 American adults with at least $1 million in investable assets.

One third of the wealthy respondents were born outside the U.S. or were first-generation U.S. citizens.

The wealth is skewed toward older generations, with one quarter of the millionaires under 40 years old, according to the report. The wealthy are also well educated, with 54 percent possessing a college degree. Only 8 percent have just a high school diploma.

“As an industry, we need to learn to cater to an increasingly diverse client base and provide them with the products and services they require, and to strive to have an employee base that reflects the communities in which we do business,” says Terry Jenkins, president and CEO of BMO Private Bank.