With a presidential election comes big speeches about Social Security and Medicare. But if you’re a cynical 40-something (or younger) like me, you’re not planning on being able to depend on those programs being viable in 20 or more years. Nope, I figure my ability to retire will rest entirely on my shoulders.

But what does that mean? How much will I need to squirrel away for my golden years? Turns out the experts offer some advice.

First off, you won’t need 100% of your salary when you retire. Depending on their situations, most retirees live on between 70% and 80% of their pre-retirement incomes. Once you decide on that percentage, you can easily calculate the amount you’ll need to have on hand when you retire.

(Editor’s note: A reader let me know that it’s unclear what I mean by savings. For our purposes here, I’m discounting Social Security and pensions, since most of us don’t have pensions and there’s no guarantee that Social Security will still be around. At the same time, I am including investments like IRAs and 401K plans. These have largely replaced pension plans and are the most often recommended ways to save for retirement. Now back to our regularly scheduled program.)

Let’s say that you earn an even \$50,000 each year. You’re a conservative sort, who figures that having 80% of that each year is a better cushion. Find 80% of \$50,000 to find your annual retirement income. (In case you’ve forgotten, of means multiplication in this situation. So you’ll need to multiply 80% — or 0.8 — by \$50,000 to get your final answer. Using a calculator works just fine.)

80% of \$50,000

0.8 • 50,000 = 40,000

In this scenario, you’re shooting for \$40,000 in the bank for every year you are retired. And that’s where the tricky part comes in. There’s no way to know for sure how many years of retirement you’ll actually have. People are living longer, which is one reason that the actual retirement age is creeping up.

But let’s assume that you are expecting the average 20-year retirement. (That sounds heavenly!) The rest of the math is incredibly simple. Just multiply the annual retirement income by the number of years:

\$40,000 • 20 = \$800,000

Yep. You read that right. With a modest \$50,000 annual income, it’s reasonable to expect you’ll need \$800,000 in the bank before you can spend your days volunteering at the hospital gift shop or planting daisies. (This is why most folks can’t afford to retire.)

So with just these simple calculations, let’s play with the numbers. What if you reduce the percent to 70% and keep the retirement time the same?

0.7 • 50,000 = \$35,000

\$35,000 • 20 = \$700,000

What about keeping the percent the same and reducing the retirement time to 15 years?

0.8 • 50,000 = \$40,000

\$40,000 • 15 = \$600,000

Let’s try one more idea: reducing both the percent and retirement time.

0.7 • 50,000 = \$35,000

\$35,000 • 15 = \$525,000

This exercise isn’t really a waste of time. (I promise.) With these four figures, you have several goals to shoot for — lowest, middle and highest goal. (Of course, having even more than \$1.2 million is just fine.) And with those three goals comes more flexibility in your savings options. If you shoot for 70% of your pre-retirement income and plan to spend 15 years in retirement, you’ll need \$525,000 in savings. If you shoot for 80% and 15 years, you’ll need \$600,000. At 70% and 30 years, you’ll need \$700,000, and at 80% and 30 years, you’ll need a cool \$800,000.

Of course deciding where to invest or save your hard earned cash is a whole ‘nother ball of wax. But knowing what you’re shooting for is a great start. Otherwise, you could miss the retirement boat completely.

Come back on Friday to get the scoop on benchmarking your retirement savings. In order to meet your goals, how much should you already have in savings at 30 years old? 40 years old? We’ll check the math.

Were you surprised to see these figures? Where they higher than expected or lower? Share your thoughts in the comments section.