Long ago, Americans could get a life-long career at a big company, make a decent living, buy a house, support a family and retire effortlessly. These days are long gone.

According to Forbes, the average life expectancy of a company on the S&P 500 used to be 75 years. Today that number is just barely 15 years. Research shows that by the year 2027, 75% of the companies on the S&P 500 will be replaced.

Too big to fall? Data collected over the last 55 years tell us otherwise.

For job seekers, especially the millennials with little work experience, this is quite alarming. So as a 20-something, how do you engineer your job security?

1. It starts with your attitude.

When I was in high school, I had a friend who worked at McDonald’s everyday after class for two years straight. Being the 16-year old dumb kid that I was back then, I asked, “Dude, why are you still working at McDonald’s? It’s not like you’re going to learn anything.”

He smiled and replied, “That’s not true. There’s always something new to learn every day. I now understand how a franchise is run, how the supply chain works, how to stay focused under pressure, how to help your colleagues succeed…” and he went on and on.

If you can see the light at the end of the tunnel, you will be able to power through any type of stress. With a strong sense of purpose and knowing exactly what you want, you will enjoy your job a lot more and you will excel at whatever it is that you do.

“Your attitude, not your aptitude, will determine your altitude.”

– Zig Ziglar

2. Be a sponge. Absorb everything.

As Gen Y’s, we are used to have information fed to us. We keep hearing, “There’s no such thing as a dumb question,” but the reality is that there are definitely dumber questions. Before you ask a question, make sure you’ve done what you can to find the answer. To avoid asking stupid questions, learn everything you can about the organization, the people, the personalities, the dynamics, the culture, the industry, the products, the office politics, the names of office puppies…EVERYTHING! Start taking your colleagues out to coffee and learn about their background, their story, and why they’re working there. Start reading up on industry news and educate yourself on the company’s milestones, competitors, and customers. Employers hire for fit, so convince them that they’ve made the right decision.

3. Under-promise. Over-deliver.

Ah! The art of managing expectations. You don’t want to under-promise in a way that makes your employer think that you are incapable of doing the job. If you think you can get the work done in three days, tell your employer four days and do it in two. But be careful, you raise the bar for yourself every single time you under-promise and over-deliver so make sure your performance is consistent and don’t bite off more than you can chew.

4. Understand your value.

In her book, The Reality-Based Rule of the Workplace, Cy Wakeman suggests a formula that attempts to quantify the value employees provide to their employers. Here’s the formula:

Your Value = Current Performance + Future Potential — 3x Emotional Expensiveness

Emotional expensiveness is your drama factor. You are emotionally expensive if you complain and judge others a lot, come to work in a bad mood, constantly seek out reward or praise for job well done or share too much of your personal life. Come to work with a professional mindset and stay focused on the tasks at hand. When your colleagues gossip, stay neutral and don’t get involved in other people’s drama. If the drama involves you, let the small things go and take the high road. Draw the line clearly and stand your ground if you have to. However, writing passive-aggressive emails and cc’ing your boss, manager, colleagues is probably the worst way you can deal with drama. You’ll just end up making a fool out of yourself.

In this day and age, job security isn’t handed to you anymore. You must engineer your own job security and make yourself irreplaceable.

Become the pedal of the car and drive both your career and your organization forward.