Half of Your Life in 9 Minutes

29 200: that's the number of days in your life, that is, if you live to the age of 80. If you sleep for eight hours a day, for 80 years, that amounts to 9733 days. In other words, sleep makes up a third of your life. If you work for eight hours a day, five days a week, for an average period of 45 years, that amounts to 3900 days. Or, 13% of your life. But, before you can go to work, you often have to attend school. Because some students attend college and others don't, let's assume an average period of 15 years spent in school. If you attend school for eight hours a day, five days a week, for 44 weeks out of the year, that amounts to 1100 days. Or, 4% of your life. If we add up these percentages, that amounts to roughly 50% of your life. So, half of your life is accounted for by sleep and work.

Knowing this information may bother you. Or, it may excite you. If it does bother you, allow me to try and change your perspective. Potentially, if we are smart about the decisions we make, with respect to sleep and work, we can get half of our life put together. So, let's start in the land of dreams.


The World Health Organization and the National Sleep Foundation recommend that individuals get 8 hoursof sleep each night [9]. However, 2/3 of adults in developed nations get less than this [9]. In other words, 66% of adults are living in a perpetual state of drowsiness.

Circadian Harmony

40% of the population are morning people, also known as larks [9]. They have a natural tendency to wake up early and sleep early; they feel the most energized early in the morning and feel sleepy early at night. 30% of people are evening people, also known as owls [9]. They have a natural tendency to wake up late and stay up late; they feel energized and sleepy later in the day than larks. The remaining 30% fall somewhere in between these two extremes [9].

Society has a bias for larks which leaves owls at a constant disadvantage. Owls are forced to wake up earlier than they naturally desire and fall asleep later than they should. As a result, they're always sleeping less than required and operating in a more drowsy state.

If you can, build a life that is in harmony with your natural circadian rhythms: you'll be better off than those who don't. But, there's also a responsibility on society and employers to make environments that are better suited for night owls. That issue aside, how can we get the best sleep each night?

Sleep Habits

Here are a few of my favorite tips from Medline Plus [14]:

- Try to sleep at the same time and get up at the same time each day, even on the weekends. This will help your body keep a consistent sleep-wake rhythm and improve your sleep quality.

- Avoid napping after 3 PM. Naps make it harder to fall asleep at night.

- Try to exercise for at least 30 minutes a day but not too close to bedtime.

- Try to get some sunlight during the day so that your sleep cycle is accurately calibrated. Try to get sunlight as soon as you wake up if possible. Conversely, try to dim the lights and avoid screen time before bed.

- Lastly, leave time to unwind before bed at the end of the day. Create a nighttime ritual that allows you to progressively get more relaxed before falling asleep.

Now that we've discussed sleep, let's move on to the next big part of life: work.


According to a poll conducted by GallUp, 85% of people don't feel engaged at work [5]. In America, this number is a little bit better at 70% [5]. In other words, a lot of people are wasting their time and potential. Imagine how much better the world would be if everyone felt engaged at work. What if everyone is present and excited when they wake up for work each day? What could we accomplish as a species? I know it sounds like I’m asking a lot, but I think getting people to feel engaged is simpler than you might think and it doesn’t require that everyone become a musician, an athlete, or a movie star.

Self-Determination Theory

According to the widely cited Self-Determination Theory (SDT), the answer to why some people love their work more than others is intrinsic motivation. Intrinsically motivated activities are things that we do because they are enjoyable like listening to music, watching a movie, or talking with a friend. The process, itself, is enjoyable; we don't need a reward for doing it.

Now, for the real question: can we have jobs that are intrinsically motivating? According to SDT, a job needs to be interesting, provide the right amount of challenge and novelty, and meet three psychological needs to produce and maintain intrinsic motivation: autonomy, competence, and relatedness [10].


Autonomy is when you feel like you have personal control over what you do, when you do it, and how you do it. In other words, you feel in control over your work and not like a slave to another.


You feel competent when you can get better at what you do and that you’re responsible for the outcomes of your actions.


And, lastly, relatedness occurs when you feel a connection to the people you work with; you care about them and they care about you.

In his book Drive, Daniel H. Pink brings up another element important for career satisfaction which I think is worth touching on: purpose.


A person's purpose is a goal, much larger than themselves, that they are working towards. According to Pink, studies done at the University of Rochester found that students who had set and achieved purpose driven goals were happier than students who had set and achieved external goals such as making a certain amount of money [11].

As you may have noticed, a satisfying career was not necessarily linked to passion, money, fame, or status. Instead, it was linked to the psychological needs of autonomy, competence, relatedness, and purpose.

Acquiring the Needs

So, how do you go about acquiring these psychological needs? What can you do, as an individual, to achieve them? In his book So Good They Can't Ignore You, Cal Newport lays outs a straightforward strategy:

- Build up your skills in an area. When the skills you have are low in supply but high in demand, you have become more valuable. In other words, you are highly competent.

- When you are highly competent and valuable, you have leverage with respect to your work; you have more choice than your employers.

- You can use this leverage to be more selective about your own hours, your own teams, and what companies you work for. As a result, you have more control over your autonomy, relatedness, and the purpose you work towards.

- To summarize, become competent at an in-demand skill, and use that competence as leverage to get yourself more autonomy, relatedness, and purpose as these are the things that make for a fulfilling career. As you become competent at an in-demand skill, the money will, of course, follow as a byproduct of your valuable nature.

Now that we’ve discussed sleep and work, we've essentially covered 50% of the average life. But, there's one more big aspect that I want to look at.

Most of Your Life

As of 2018, there are approximately 7.6 billion other humans you could get to know [4]. Of these 7.6 billion, you will meet 10s of 1000s. Of these thousands, there will be - at any one time - roughly 1500 whose names and faces you could recognize [3]. Of these 1500, there will be 150 who you have a fairly good reciprocal relationship with [3]. These people will make up your core social group and this number is referred to as Dunbar's Number. Of these 150, there will be roughly five who you are really close to and whom you interact with almost daily [3]. The people in these groups will likely fluctuate throughout your life and, based on data presented in The Atlas, it might fluctuate as follows [13].

Early in your life, most of your time will be spent with friends and immediate family. As you transition into adulthood, the amount of time you spend with friends and family declines quite a bit, and most of your time is spent with your co-workers, your kids, and your partner. And, as you enter old age, most of your time is spent with your partner or alone.

There are so many ways to look at and interpret this data. I encourage you to take a look at the original graphs, linked in the description, and decide what it all means to you. But, I'll share some insights that I have pulled out from the data.

Insight #1 - Description, Not Prescription.

My first insight is that this data is descriptive, not prescriptive; it’s a representation of how things are but not how they should be. While the average person does spend most of their time with their family from the ages of 15-30, there isn't any reason I couldn't spend more. For example, this data might be a good indicator that I should plan annual family vacations and get-togethers so that I ensure that I am spending as much quality time with my family as I can. It's so easy to get caught up in the everyday problems & ambitions of our lives that we can go years without spending quality time with the people close to us. And, before you know it, they could be gone.

Insight #2 - Important Decisions

My second insight is that picking good co-workers and a good partner are among the most important decisions we can make in a life. These are the people whom most of us will spend the greatest amount of time with.

Insight #3 - Make Peace

My final insight is that it's important to make peace with yourself. Most of your life will be spent alone, especially in the final years. So, it's important to learn how to live with yourself, know yourself, and live true to yourself so that you can be comfortable, or even happy, in your own mind.

These are just some insights that I have pulled from the data, but I would be interested in hearing what you got out of it in the comments.


So, that’s the mathematics of your life, or at least half of it. If you sleep well, put some thought into your career, wisely choose the people around you, and spend time with your loved ones, I think you'll come to the end of it pretty satisfied. And hey, there's still the whole other half that we didn't even discuss. As always, thanks for watching and I'll see you next time!



01: “List of Countries by Life Expectancy.” Wikipedia, Wikimedia Foundation, 17 May 2018

02: Table 1. Time Spent in Primary Activities and Percent of the Civilian Population Engaging in Each Activity, Averages per Day by Sex, 2016 Annual Averages.” U.S. Bureau of Labor Statistics, U.S. Bureau of Labor Statistics, 27 June 2017

03: Dunbar, Robin. “How Many ‘Friends’ Can You Really Have?” IEEE Spectrum: Technology, Engineering, and Science News, IEEE Spectrum, 31 May 2011

04: Current World Population.” Philippines Population (2018) - Worldometers

05: Gallup, Inc. “The World's Broken Workplace.” Gallup.com, 13 June 2017

06: Marriage and Divorce: Patterns by Gender, Race, and Educational Attainment : Monthly Labor Review.” U.S. Bureau of Labor Statistics, U.S. Bureau of Labor Statistics, 1 Oct. 2013

07: Ghule, Amit, et al. “Sleep Statistics - Latest Research & Data.” American Sleep Assoc

08: Jommore, et al. “Sleep Deprivation - Latest Research & Treatments.” American Sleep Assoc

09: Walker, Matthew P. Why We Sleep: Unlocking the Power of Sleep and Dreams. Scribner, an Imprint of Simon & Schuster, Inc., 2017

10: Deci, E. L., & Ryan, R. M. (2000). The "what" and "why" of goal pursuits: Human needs and the self-determination of behavior. Psychological Inquiry, 11(4), 227-268.

11: Pink, Daniel H. Drive: The Surprising Truth About What Motivates Us. New York, NY: Riverhead Books, 2009.

12: Reebok. “Reebok Survey: Humans Spend Less Than One Percent Of Life On Physical Fitness.” PR Newswire: News Distribution, Targeting and Monitoring, PRNewswire, 3 May 2016.

13: Kopf, Dan. “Who Americans Spend Their Time With.” Atlas, Quartz, 21 June 2017.

14: “Tips for Getting a Good Night's Sleep | NIH MedlinePlus the Magazine.” MedlinePlus, U.S. National Library of Medicine.