14. Examine whether your situation will require caregiving for a loved one

In other cases, it's not you who's in bad health but a spouse or loved one for whom you have to provide care. The authors note that 20% of those who leave the workforce earlier than planned did so to care for a loved one.

And even if you don't leave the workforce, this still might cost you. You might have to hire a caregiver, for instance.

Yes, you might be able to take advantage of the Family and Medical Leave Act, but that's not a long-term solution. Also, if you don't have it, consider buying long-term-care insurance to cover this kind of expense or commitment. Having a policy in place could help you identify your optimal retirement age.

15. Are you concerned that future health limitations will interfere with personal retirement goals?

Plenty of folks think they should retire while they are still healthy and can enjoy retirement. But don't let fears of later health problems dictate an earlier retirement, the Tacchinos write. "Some (people) choose a retirement age based on their perception that they only have so many good years left and they want to enjoy some time with good health in retirement."

Remember, research has shown that your perception of your health will typically have a stronger effect on your retirement-age decision than the actual, medically determined status of your health, the authors write.

16. Evaluate whether you will need to retire to raise grandchildren

About 6.3% of children under age 18 are living with grandparents. Is this in your future? If so, consider how you might have to keep working to afford to raise grandchildren, the Tacchinos write. Or consider how you might have to retire to care for the grandkids.

17. Appraise the likelihood of your job ending suddenly and prematurely

What are the odds that you'll be laid off or become unemployed for other reasons? Consider whether you are at risk of losing your job. Older workers may have their position or shift abolished, AARP's Public Policy Institute points out. In other cases, there's not enough work, or a plant or company closed down or moved.  

18. Assess job satisfaction and potential changes in job satisfaction

Being unhappy with your work is not the best way to determine your ideal retirement age, but it's certainly a factor. Try to get a handle on whether you really want to quit the job or whether your employer is trying to get you to leave.

19. Understand how to determine an appropriate retirement date and broaden your expectation

"Perhaps the trickiest and most subjective set of considerations to analyze centers around (your) own personal psyche," the authors write. "In essence, (your) mindset is ultimately responsible for driving the desired retirement age."

For instance, you might plan to retire after you turn 65. Instead, you might want to set your retirement age in other ways: years until death (your remaining life expectancy) or your work/retirement ratio (75% work/25% retirement), the authors write.

"Why should chronological age be the deciding factor?" the authors ask.

20. Evaluate your ability to adapt to retirement

What's your self-efficacy? Do you think you will be able to cope with the changes that come with retirement? If you can predict your level of comfort and you think you will be able to adapt, that's a good thing, because it's a major factor in determining your retirement age, the Tacchinos write.

"One researcher theorized that some who view themselves as unable to adjust to retirement either recognize their own need to work to feel good about themselves or (subscribe) to the belief that retirement is a time of dissatisfaction, isolation, and decline," the authors write.

21. Assess the identity, fellowship and status you receive from working

It's quite possible your work defines who you are, you derive a sense of self-worth from working, and you might find it hard to retire. In other cases, you might want to keep working because you enjoy the job and want to keep busy.

"Consider that while most (people) value the retirement lifestyle, they may not realize what they are losing by ending the work lifestyle," the authors write. "It is important for (people) to discern exactly what the loss of their main job will do to their sense of self. Unfortunately we often do not realize what we have until we no longer have it."

22. Determine your willingness to work

If you're unsatisfied with the day-to-day grind of working, that's going to drive your decision to retire, whether it's the optimal time or not.

23. Determine your desire for leisure

If what you want is a life of leisure, this too might drive your decision to retire early. Just remember, "It is important for (you) to imagine the daily routine brought about by a lifestyle of leisure," the authors wrote. "Filling up free time with meaningful activity requires thought and planning."

24. Weigh the balance between work satisfaction and retirement satisfaction

According to the Tacchinos, the difference between your current satisfaction with your work and your anticipated satisfaction in retirement can predict your anticipated retirement age.

25. Examine the potential for joint retirement

Lastly, you are probably not making the decision to retire by yourself. The choice between work and retirement may be related to your ability to retire with your spouse, the authors write.

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