According to Scottrade Inc.’s 2012 American Retirement Study, this is up from 34% that were concerned about having to work in retirement in 2011.

Forty-one percent of respondents are concerned that their investments won’t generate enough money to cover living expenses, up from 32% in 2011. Also, 38% are concerned they will outlive their retirement savings, up from 31% in 2011.

Americans’ general concern with having enough money for retirement hit a six-year high. More than half, at 57%, reported they are either extremely concerned or very concerned with this issue, up from 47% in 2011 and 56% in 2007.

As a result, the majority of Americans (56%) think generating income during retirement is more important today than it was a year ago. The reason, according to 67% of those respondents, is simply an expectation that the cost of living during retirement will be more expensive. This is leading 38% of all survey respondents to structure their portfolio to include income-generating investments.

While the majority of survey respondents over the age of 55 strongly agreed that given the opportunity to do it over, they would have started saving for retirement at a younger age, roughly a quarter said they would have become more educated about planning for retirement. Learning from their regret, more Americans (35%) expect to seek out information to learn more about retirement planning in 2012, compared to 28% in 2011. When looking at the responses by generations, the younger groups—Gen Y and Gen X—led this educational drive with 40% and 44%, respectively, stating they will seek out information in 2012.

The survey was commissioned by Scottrade and conducted online by Synovate and was fielded with a nationally representative sample of 1,000 respondents from January 5 to 9, 2012.