In a post on Wait But Why last year, Tim Urban laid out the human lifespan visually.

Now he talks about what that means for relationships:

What I’ve been thinking about is a really important part of life that, unlike all of these examples, isn’t spread out evenly through time—something whose [already done/still to come] ratio doesn’t at all align with how far I am through life:

Relationships.

I’ve been thinking about my parents, who are in their mid-60s. During my first 18 years, I spent some time with my parents during at least 90% of my days. But since heading off to college and then later moving out of Boston, I’ve probably seen them an average of only five times a year each, for an average of maybe two days each time. 10 days a year. About 3% of the days I spent with them each year of my childhood.

Being in their mid-60s, let’s continue to be super optimistic and say I’m one of the incredibly lucky people to have both parents alive into my 60s. That would give us about 30 more years of coexistence. If the 10 days a year thing holds, that’s 300 days left to hang with mom and dad. Less time than I spent with them in any one of my 18 childhood years.

When you look at that reality, you realize that despite not being at the end of your life, you may very well be nearing the end of your time with some of the most important people in your life. If I lay out the total days I’ll ever spend with each of my parents—assuming I’m as lucky as can be—this becomes starkly clear.

It turns out that when I graduated from high school, I had already used up 93% of my in-person parent time. I’m now enjoying the last 5% of that time. We’re in the tail end.

It’s a similar story with my two sisters. After living in a house with them for 10 and 13 years respectively, I now live across the country from both of them and spend maybe 15 days with each of them a year. Hopefully, that leaves us with about 15% of our total hangout time left.

The same often goes for old friends. In high school, I sat around playing hearts with the same four guys about five days a week. In four years, we probably racked up 700 group hangouts. Now, scattered around the country with totally different lives and schedules, the five of us are in the same room at the same time probably 10 days each decade. The group is in its final 7%.

So what do we do with this information?

Setting aside my secret hope that technological advances will let me live to 700, I see three takeaways here:

1) Living in the same place as the people you love matters. I probably have 10X the time left with the people who live in my city as I do with the people who live somewhere else.

2) Priorities matter. Your remaining face time with any person depends largely on where that person falls on your list of life priorities. Make sure this list is set by you—not by unconscious inertia.

3) Quality time matters. If you’re in your last 10% of time with someone you love, keep that fact in the front of your mind when you’re with them and treat that time as what it actually is: precious.

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