Sixty-four percent of millennial investors said they have a financial plan, yet 68 percent said they are not investing enough for retirement, according to a recent survey by the Nationwide Retirement Institute.

“Millennials are saying they are investing, their minds are focused on the financial markets and their financial plan,” said Mike Spangler, president of Nationwide’s mutual funds business.

Yet the survey found 36 percent of millennial investors (aged 18 to 35) only guess at how much they need to fund their retirement, and nearly one in four do not know if they have a 401(k) plan.

While 58 percent of millennials conduct their own financial research and make their own investment decisions, only half are confident they know how much to save for retirement.

For those millennials without a financial plan, 28 percent feel that creating a financial plan is overwhelming and 40 percent responded, “they haven’t gotten around to it yet.”

In addition, 56 percent of millennial investors think they would be more financially successful with professional financial advice. But they are more likely to consult family (50 percent) and websites (49 percent) than a financial advisor (39 percent) for their financial planning needs.

“The survey tells us they are open to advice and believe advice can benefit them. But, I believe it is important that an advisor talk with them not to them.” said Spangler.

Harris Poll conducted online interviews with 2,033 investors aged 18 and older between June 11, 2014 and June 30, 2014. The study participants are financial decision-makers in their households and have investable assets of at least $50,000.