Elderly Woman Looking Out a Window © Keith Brofsky, Photodisc, Getty Images

The average American who lives to the ripe old age of 100 will spend $3.5 million in his or her lifetime, according to an analysis of data from the Bureau of Labor Statistics. A good chunk of that, more than $1.5 million, will have been racked up by your 50th birthday. The following 30 or so years -- the average 50-year-old today can expect to live until 81 -- will run an additional $1.4 million. And the lucky few who make it to 100 will need an extra $630,000.

Experts say these high costs of living often come as a shock to retirees, many of whom expect to dramatically cut back on their living expenses as they get older and stick to a fixed budget. "A lot of time people actually end up spending more money in retirement than they may have spent when they were working," says Heidi Schmidt, a wealth manager in Dallas with USAA. (Are you saving enough for retirement? Find out with MSN Money's calculator.)

Just where that money goes depends largely on your decade. Most people in their 60s spend a lot of their savings on entertainment -- finally buying that sailboat or splurging on trips to the Caribbean. Those in their 80s, on the other hand, typically swap a good portion of their leisure budget for medical bills.

Of course, not all expenses come down to age, experts say. A healthy octogenarian with wanderlust might have spending habits more in line with people 20 or 30 years younger. And certainly many Americans will spend much less in retirement -- through either careful planning, good luck or both. Whatever the retirement goals, here's a breakdown of how spending tends to vary through the retirement years.

60s

  • Housing (mortgage, utilities and decor): $155,500.
  • Furnishings and appliances: $15,000.
  • Entertainment and eating out: $46,700.
  • Transportation: $71,000.

In this decade of transitioning into retirement, 60-somethings spend more than older age groups on everything from housing to clothes. Many who retire in their 60s find themselves with the time -- and savings -- to finally splurge a little on travel or a big-ticket item like a car. Or to indulge their favorite hobbies: According to the Bureau of Labor Statistics, the average recently retired American spends $2,300 a year on activities like going to the movies, caring for a pet and buying the latest gadgets. That drops to an average of $1,300 after age 75.

70s

  • Total health care costs: $48,400.
  • Prescription drugs: $8,100.
  • Household repairs: $16,400.
  • Utilities: $33,900.

Aging's challenges can come with big price tags. When people hit their 70s, health care costs begin to spike. Longer life spans and the rise of chronic illnesses have pushed up national health care spending, according to the Kaiser Family Foundation. People in their late 60s and early 70s spend an average $4,900 a year on health care, an increase of almost 30% from people in their late 50s and early 60s, according to the Bureau of Labor Statistics. Adding to the burden, health care costs are expected to grow faster than income over the coming years, according to Kaiser.

80s

  • Health insurance: $30,300
  • Entertainment and eating out: $26,000
  • Groceries: $26,400
  • Gasoline: $9,800

Eighty-somethings spend 57% more on health insurance and half as much on entertainment as folks in their 50s. More retirees are saving money in their later years by moving in with their adult children. A survey by the Pew Research Center released in 2010 found that 21% of adults age 85 and above live in a multi-generational household that includes at least two adult generations or a grandparent. That is up from 17% of people in their late 40s and early 50s.

90s

  • Nursing home (private room): $87,200
  • Out-of-pocket long-term care: $14,000
  • Assisted living: $89,000
  • Adult day services: $36,400

Health costs grow exponentially from one's 50s to mid-90s. And America's 1.9 million nonagerians depend heavily on Social Security and pensions. But Social Security may come up short by the time most baby boomers are in their 90s: The Social Security Administration has already started tapping its trust fund to cover benefits, and current projections estimate that Social Security will have enough funds to cover only 75% of scheduled benefits after 2036.

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