For better or worse, Social Security is America's most important program with regard to providing a financial foundation for seniors. Each month, nearly 45 million senior citizens receive a Social Security benefit.
A majority of them are eligible for the retired worker benefit. And despite this average benefit totaling just $1,411, it proves to be more than enough to keep more than 15 million seniors out of poverty.
Another overlooked fact about Social Security is that it's a program that can stand the test of time. Even with the latest Social Security Board of Trustees report signaling troubled waters ahead for the program (Social Security's $2.9 trillion in asset reserves are projected to be completely exhausted by 2034), it is in absolutely no danger of running out of money.
In fact, short of Congress changing how the program is funded, Social Security can never go bankrupt. That's a pretty comforting feeling if you're a current retiree or a working-age American looking to retire in the years or decades ahead.
The three ways Social Security generates revenue
Last year alone, the Board of Trustees report shows, the program essentially generated $1 trillion in income -- $996.6 billion, to be precise. How did Social Security come up with so much cash for beneficiaries? Let's take a closer look.
1. The payroll tax: Social Security's saving grace
The importance of Social Security's payroll tax simply can't be overstated. Without this tax on wage income, Social Security wouldn't be a time-tested social program. In 2017, the payroll tax generated $873.6 billion of the $996.6 billion collected. On a percentage basis, that's 87.7% of all revenue collected in 2017, up slightly from the 87.3% of the $957.5 billion collected in 2016.
Though the maximum taxable earnings cap is often adjusted annually, on par with the increase in the National Average Wage Index, the 12.4% payroll tax applies to earned income up to $128,400, as of 2018. This means those relatively few people who earn more than $128,400 in 2018 will escape Social Security's payroll tax on any income above this level, while more than 90% of working Americans pay into Social Security on every dollar they earn.
It's also worth pointing out that Social Security's 12.4% payroll tax isn't entirely applicable to most people. If you're employed by someone else, your employer covers half your liability (6.2%), with you responsible for the other half (6.2%). Only folks who are self-employed are responsible for the full 12.4% payroll tax.
2. The taxation of benefits: Social Security's necessary evil
On the other end of the spectrum is Social Security's smallest revenue contributor: the taxation of benefits. In 2017, taxing Social Security benefits allowed the program to generate $37.9 billion in income, or 3.8% of total revenue.
In 1983, Congress overhauled Social Security, and among the changes made was the introduction of a tax on Social Security benefits above a certain adjusted gross income level. If one-half of your Social Security benefits, plus all your earned income, totaled above $25,000 as a single taxpayer, or $32,000 as a couple filing jointly, up to 50% of your Social Security benefits could be taxed. In 1993, a second tax tier was added that allowed up to 85% of a person's or couple's Social Security benefits to be taxed if one-half of their benefits plus earned income was more than $34,000 or $44,000, respectively.
One of the biggest complaints against the taxation of benefits is that the aforementioned income thresholds haven't been adjusted in 35 years! Not to mention, taxing benefits could be hurting middle-income seniors and couples who rely on Social Security to make ends meet.
Then again, the taxation of benefits is a necessary evil that helps put cash into Social Security's coffers. As much as seniors would like to see this archaic tax go away, doing so would create an immediate revenue shortfall for the program, likely leading to a much sooner asset-reserve depletion date.
3. Interest income on asset reserves: Social Security's disappearing income stream
The third and final revenue source is the interest income earned by Social Security's asset reserves. In 2017, the program generated $85.1 billion in revenue, or 8.5% of total revenue.
Rather than let these asset reserves -- built up over the past 35 years -- simply sit there, the Social Security Administration takes this excess cash and purchases special-issue bonds, and to a lesser extent certificates of indebtedness, from the federal government. In doing so, the federal government is able to fund its general activities (selling bonds is a common way it does this), and Social Security is able to generate interest from the U.S. government. It's a win-win for both parties. As of the most recent update, Social Security's asset reserves were earning an average of 2.9%.
Unfortunately, this source of income isn't as guaranteed as Social Security's payroll tax and the taxation of benefits. It relies on there being asset reserves with which to earn interest. With the program already spending more than it's generating, it's estimated to be just 16 years until Social Security's asset reserves are completely gone. When these disappear, so will the program's interest income.
The bottom line: Social Security is here to stay, even if its current payout schedule isn't sustainable.
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