Investor optimism over their retirement readiness quickly fades with age.

That's one of the notable takeaways from the fifth annual Wells Fargo Middle-Class Retirement study released on Wednesday.

Almost half of the 1,000 middle-income Americans surveyed (48%) said they lacked confidence that they had saved enough for retirement. Among the older crowd—those between ages 50 and 59—the lack of confidence was much more prevalent, with 71% saying they hadn't saved enough "to live the retirement lifestyle they want."

Older Americans were also more likely to feel depressed about their retirement prospects. One in three middle-class Americans in their 40s and 50s felt depressed, compared with only 25% of middle-class Americans overall who felt that way. Other indicators of diminished retirement expectations among older middle-income Americans include:

  • Half of the respondents in their 50s said they will need to work until they're 80, compared with only 33% of all respondents who predicted having to work so long.
  • Nearly half (48%) of middle-class Americans in their 50s feared not having enough money to survive on in retirement, compared with only 31% who said so overall.

Though older Americans were more worried about their retirement, they were less likely to be taking measures to address their concerns.  For example, 41% of respondents between 50 and 59 said they were not currently contributing anything to a 401(k), and IRA or other retirement savings vehicle, compared with 34% of all respondents who said the same.
Overall, most middle-income Americans were not killing themselves to save for retirement, with 61% admitting they were not sacrificing a lot to save. According to the study, respondents across all ages saved a median of $20,000.  The median amount saved by those in their 40s was $40,000; for those in their 50s, the median was $20,000; and for those 60 to 75, the median was $25,000.

"Saving for retirement isn't easy. It requires sacrifice, and it's not something people can push off and hope to achieve later in life," Joe Ready, director of Wells Fargo's Institutional Retirement and Trust, said in a statement.

The study is based on a telephone survey of 1,001 middle-class Americans between the ages of 25 and 75 with a median household income of $63,000. The survey was conducted from July 20, 2014 to August 25, 2014.

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