Saving for — and even defining — life after work can vary greatly among generations.

According to a new Merrill Lynch study, nearly three-quarters (72%) of adults 50-plus say an "ideal" retirement will include working. Meanwhile, millennials in their early 30s and younger are more concerned with retiring debt than saving for retirement, according to Wells Fargo research.

Financial strategies to achieve retirement goals reflecting these generational differences often require age-suitable customization.

Managing expectations

"The older generations sometimes still have pensions. Even if they are small they count," says Brian Kuhn, a financial planner in Fulton, Maryland. "And they also are still reasonably confident they're going to get something out of Social Security. So helping them invest is about achieving a growth rate necessary to bridge that gap between these income sources and what they need to live on. For the younger generation it is about managing expectations of what invested money may do over time, based on what they are able to contribute."

Kuhn attempts to inspire retirement saving among younger clients by encouraging them to "hide money from themselves" in as many places as possible, including employer-sponsored 401(k)s, Roth IRAs, Health Savings Accounts, bank savings accounts and 529 plans.

David Hunter, an independent adviser in Asheville, North Carolina, tells his clients to think in terms of baby steps — small moves toward saving where they can see the initial benefits and then ramp up from there.

"I have a young professional couple in their early 30s," Hunter says. "They have been saving maximum amounts to Simple IRAs or 401(k)s since they've been married. They have already accumulated over $200,000 and are even more excited about compounding the savings for early retirement goals."

Some advisers urge their young clients to save even more aggressively. A financial planner in Merritt Island, Florida, Steven Podnos offers a blunt recommendation to those he advises: "I tell them they need to save 20% plus of their income in order to have some 'choices' later on. I have a client that saved almost half of his annual income for 25 years. He was able to tolerate a medical retirement at age 60 with no fear of not having enough money."

More in common than you might think

While younger generations are often encouraged to invest more aggressively, in light of their long-term savings shelf-life, many millennials have portfolios surprisingly similar to senior investors.

"Some younger clients are more conservative than investors twice their age," notes Brian Kuhn. "The older generation — if they have been investing a while — have seen it work for them. The younger generation, perhaps not."

It's a trend confirmed by research released earlier this year by global wealth management firm UBS. The study reported that Gen-Y adults are "the most fiscally conservative generation since the Great Depression."

Growing up amid the rubble of the global financial collapse, one-third of Millennial investors describe their risk profile as "conservative" or "somewhat conservative," according to the report. In reality though, their investment holdings are extremely conservative, holding an average of 52% in cash, compared with a general cash allocation of 23% for older investors.

However, some investment tactics apply to everyone, according to Larry McClanahan, a portfolio manager based in Portland, Oregon. McClanahan says an overheated market is like an overvalued vehicle.

"When asset classes are very overpriced, I dial back the risk of exposure for clients of all ages," he says. "Whether you're 32 or 62, you wouldn't pay $38,000 for a Toyota Camry that's only worth $28,000 just because you have a 'long enough time horizon.' So then why do we check our brains at the door when it comes to overpaying for financial assets? Valuation is the trump card."

The challenge for late-stage savers

Meanwhile, late-stage savers are often faced with time — and math — stacked against them.

"While having time on your side is ideal, it is not always realistic," says Nicholas Phelps, a fee-only financial planner in State College, Pennsylvania. "As time goes on, the savings rate becomes relatively more important than the rate of return. But it is never too late, and if expenses can be managed or reduced then older savers may have the ability to save a large percentage of their income that wouldn't be realistic for many younger people."

Phelps adds one more piece of advice: "Maximize a Roth IRA every year, on top of other savings or group retirement plans. This relatively small effort can make an impressive difference over time."

Michael Keeler, a financial planner in Las Vegas, advises pre-retirees to analyze their cash flow. One client did just that and was surprised to learn how much he had been spending on eating out — several hundred dollars a month that could be redirected to savings. Moves like that really add up.

"We recently received a call from a client nearing retirement who added up all his statements. He couldn't believe how much money he had saved! He called to verify his numbers and I told him he was right," Keeler says. "I asked him if it was hard to save money every month. He said that it was tough at first, but once he got used to it, it wasn't a big deal. They didn't go out to eat as much or they went to cheaper restaurants. Once he saw the growth of his investments, it became even easier to increase his monthly contributions."

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