Key Takeaways:

Most of today's college grads won't be able to retire until 73 due to high debt load  12 years later than the current average retirement age

Given a life expectancy of 84, grads will only have 11 years to enjoy retirement

The median debt load of $23,300 will cost students over $115,000 (in today's dollars) by the time they retire

Employer 401(k) matches are crucial, and will compose 50% of retirement savings
Student Debt Will Follow Graduates to Retirement
With the total amount of outstanding student debt approaching $1 trillion, the plight of debtstraddled college students is more important than ever. In the past 30 years, not only has the number of high school graduates enrolled in fouryear universities increased by 11%, but college tuition has also soared over 200%. As more students attend college at a cost higher than ever before, Millennials have increasingly turned to loans to help finance their education. While much of the college debt dialogue is over immediate issues like employment and repayment, there is another glaring challenge that graduates will have to deal with for years to come: retirement.
When will students be able to retire given that many are spending the first ten years (or more) of their careers paying off their hefty loans? NerdWallet conducted a study that examined the financial profile of a typical college graduate and found that while retirement is certainly not impossible, for most it will have to wait until their earlytomid 70s  over 10 years later than the current average retirement age of 61.
Quick Facts on Students and Their Debt
Here are some quick facts to give context on exactly what students are grappling with:

Median debt for a student upon graduation: $23,300

Percentage of students who are unemployed at graduation: 18%

The median starting salary for those who do have jobs: $45,327

Standard loan repayment plan: 10 years

Average yearly loan repayment: $2,858

Number of college graduates currently estimated to be in default: Over 7 million
$23,300 in Loans Ends up Costing $115,096 by Retirement
The goal of the study was to find realistic retirement projections for the typical college graduate and create projections that applied to a broad range of students. The study compared three different financial profiles: the median graduate, with median debt and salary; the struggling graduate, with high debt and a below average salary; and the welloff graduate, with low debt and an aboveaverage salary.
Graduate Retirement Outcomes
Clearly, student debt has an impact on retirement outcomes. Currently, the average retirement age is 61. But for most of today's college grads, the realistic retirement age will be closer to their mid70s. Given an average life expectancy of 84, this will leave only 10to12 years for people to spend in retirement. The main reason for this is that although the median college graduate leaves with a seemingly manageable $23,300 debt load, 7% of a student's earnings go toward yearly loan payments of $2,858 for the first ten years of his or her career. This prevents any meaningful contributions toward retirement. In fact, by the age of 33, when the typical college grad has finally paid off their standard 10year loans, he or she can only be expected to have saved $2,466 for retirement  over $30,000 less than if the student had graduated with no debt. Even worse, the foregone savings carry a serious opportunity cost as this money would have been earning a compounded rate of return every year until retirement. At the projected retirement age of 73, the lost savings directly attributable to student debt is $115,096, nearly 28% of total retirement savings.
Surprisingly, for the struggling graduate, the retirement outcome isn't dramatically different. Despite being in nearly twice as much debt and starting with 10% less pay, the expected retirement age is still just 75, only two years later than the median case. The main reason for this is social security. Much has been discussed about whether or not social security will be around by the time Millennials retire. To be conservative, social security benefits are factored into the study at $11,070 (75% of current average) per year beginning at age 67. That said, a substantial reduction in benefits or the disappearance of the program altogether would significantly alter the retirement equation. If the current social security payouts were to remain unchanged for the next 50 years, the benefits would provide future retirees a significant boost by covering nearly 15% of their required yearly income in retirement.
Welloff Grads Retire 7 Years Earlier
The retirement prospects for the welloff grad are significantly better than the others as illustrated in the graph above. By graduating with a reduced debt load and landing a job that pays 22% more, the welloff grad can expect to retire at age 67. This is a huge departure from the other cases, and this scenario demonstrates the importance of contributing to a retirement plan early on in one's career. Compared to the median grad, the extra $40,406 that the welloff graduate is able to contribute during the first ten years of his or her career results in a $446,452 difference in retirement savings by age 73.
So How Do You Beat the Odds?
Given these circumstances, should students resign themselves to an eternity of work with little to look forward to in their latter years? Not necessarily. Though an increasing retirement age does appear to be an inevitable economic reality, being conscious of this problem and tailoring financial and career planning accordingly can go a long way toward achieving retirement objectives. There are many factors that influence the ultimate age at which people are able to retire, but there are a few variables that have a particularly large impact. Making aboveaverage yearly contributions to a retirement account, working for an organization with a decent 401(k) match, and making sure to invest money in index tracking mutual funds are three ways to help add years to retirement.
Employer 401(k) Match Is Crucial
As fewer and fewer companies offer defined benefit plans, Millennials will have to depend upon employer 401(k) plans to save for retirement. According to a recent Fidelity survey, the current median yearly matching contribution is $3,420. As shown below, these employer contributions are expected to make up roughly 50% of the retirement equation for Millennials. By working for a company that offers a yearly matching contribution of $4,420 ($1,000 more than the median), potential retirees can reduce their expected retirement age by up to three years.
401(k) Match Composes Half of Retirement Savings
Make Aboveaverage Contributions To Retirement Accounts
While working for a generous employer can do wonders for retirement, not everyone is in a position to be overly selective about whom to work for. Another important component of retirement planning is the yearly contribution rate. Making aboveaverage contributions can significantly improve retirement outcomes. Though the study projects a 6% annual posttax contribution (the average personal savings rate for Americans), increasing that number to 10% reduces the expected age of retirement from 73 to 69.
Invest In Index Funds
Contributing money towards retirement won't be helpful if the money is simply left in a savings account or a CD. To earn a return, Millennials need to be willing to take some risk and construct an equityoriented portfolio. This may be difficult for today's grads who have seen the stock market seemingly implode every five years, but unfortunately, retirement will be impossible if people invest too conservatively. The study assumed a 6% yearly return on retirement savings, which is a conservative figure given the historical performance of the market. That said, it is a rate of return that can't be achieved by completely avoiding equity exposure. The best way for an individual to overcome this problem is by investing in index tracking mutual funds, which will offer a market return with low fees.
Retirement Isn't Hopeless, But It Will Be Difficult
Far more than their parents, Millennials will have to rely upon proactive financial management to achieve their retirement goals. Each generation is afflicted with distinctive financial ills, but the challenge of college debt is unique to Millennials. The decline of pension plans, the uncertainty surrounding social security, and the college debt epidemic have placed the onus on graduates to make conscious, forwardthinking decisions about their retirement.
Methodology
Future retirement statistics were projected by profiling three potential situations that students might find themselves:

The median graduate, with median student debt and median starting salary.

The struggling graduate, with a high debt load and a belowaverage salary.

The welloff graduate, with a low debt load and an aboveaverage salary.
The study factored in a range of other relevant variables to create the projections:

Average 2012 social security benefit.

Average 2012 401(k) match.

30year average national salary growth rate.

30year average inflation rate.

30year annualized S&P 500 returns.

30 year average personal savings rate.

2012 Stafford loan interest rates.

Standard loan repayment terms.
All projected figures are inflation adjusted and discounted back to 2013 dollarterms.
Data Sources:
Bureau of Economic Analysis
Bureau of Labor Statistics
Fidelity Investments
National Association of Colleges and Employers
New York Federal Reserve
Pew Research Center
Social Security Administration
World Bank
Consumer Financial Protection Bureau
Editor's note: This story by Joseph Egoian originally appeared on NerdWallet.
To read more from NerdWallet, see:
Study: 9 in 10 Americans Underestimate Their Hidden 401(k) Fees
Early Withdrawals from 401(k)s: Should You Do It?
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