The Social Security Trustees just released their latest report, and the outlook isn't great. The program's trust funds are set to run out by 2034, and if Congress doesn't intervene with a fix, recipients could see their scheduled benefits reduced by 21%. And that's obviously a pretty big hit.

But troubling as that news might be, an even greater concern is that 34% of current recipients rely on Social Security to provide 90% to 100% of their income. And the fact that nearly half of households have no retirement savings means that millions of Americans will come to depend on those benefits just as heavily. And that's a mistake that could ruin them in retirement, even if benefits don't get cut at all.

Social Security card

IMAGE SOURCE: GETTY IMAGES.

You can't live on just Social Security

One of the greatest myths surrounding Social Security is the notion of being able to live off of those benefits in retirement without any sort of additional income stream. So let's cut straight to the chase: Social Security alone won't sustain you in retirement. It won't even come close. And if you're thinking you'll live frugally or cut back on expenses once you no longer have a paycheck coming in, consider how difficult that might be to do at present, and now imagine yourself having to uproot your lifestyle at 70, 75, or 80 when you're apt to have much less patience for major changes.

Many workers assume that their expenses will magically go down in retirement, but the reality is that living costs largely stay the same for seniors since the need for housing, food, utilities, transportation, clothing, and healthcare still exists at the same level. In fact, healthcare is the one expense that will probably go up for most seniors in retirement, since aging tends to bring about a host of medical issues that younger folks don't typically deal with.

All told, the average senior should expect to need roughly 80% of his or her previous income to pay the bills in retirement. But Social Security will only cover about half of that, assuming benefits don't get slashed. If they do, the program will cover even less. And that's why it's crucial to focus less on potential benefit cuts and more on actually saving for retirement -- because while you can't control the former, you can certainly take the latter into your own hands.

A little savings can go a long way

Many workers don't save for retirement because they feel it's unnecessary, but as we just saw, that's far from true. Others, however, neglect their nest eggs because they feel that the prospect of amassing savings is far too daunting. After all, how can an average worker get anywhere close to having enough money to retire comfortably?

The answer, however, boils down to giving yourself the lengthiest possible savings window and making modest, but steady, contributions over time. Imagine you're able to sock away $400 a month from this point forward and invest that money at a 7% average yearly return, which is more than doable with a stock-focused strategy. Here's what your savings might amount to, depending on how long you have between now and retirement:

If You Start Saving $400 a Month at Age:

Here's What You'll Have by Age 70 (Assumes a 7% Average Annual Return):

25

$1.37 million

30

$958,000

35

$663,000

40

$453,000

45

$303,000

50

$197,000

TABLE AND CALCULATIONS BY AUTHOR.

Even if you're dealing with a relatively narrow savings window -- say, you're already 50 -- you still stand to accumulate nearly $200,000 without getting close to maxing out an IRA or 401(k). And while $200,000 doesn't have quite the same ring as $1.37 million, which is what you'd get in the above scenario if you were to give yourself 45 years to save, it's certainly better than nothing.

Another thing to remember is that if you are going to rely heavily on Social Security to pay your bills in retirement, you should do your part to boost your benefits as much as possible. This means holding off on filing past your full retirement age and increasing your benefits by 8% a year as a result. Though this incentive runs out at age 70, if you're looking at a full retirement age of 67, you have a solid opportunity to increase your benefits by up to 24% -- for life.

Right now, we don't know exactly what the future holds for Social Security. Maybe benefits will get slashed. Maybe Congress will jump in and save the day. But what we do know is this: Those benefits alone won't cut it in retirement. And the sooner you realize that, the sooner you can take steps to make up for it.

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