# How do Mathematics Videos Age?

*December 15, 2018*

**Nicholas Bartlett and Yoni Nazarathy**

Do mathematics theorems age and become obsolete? Generally "no". As the field is based on axioms and logical deductions, what was true hundreds or thousands of years ago, remains true today.

How about mathematics videos? After all, mathematics on YouTube is big business. There are dozens of quality channels and tens of thousands of videos. Do mathematics videos age? Are older mathematics videos losing relevance?

At One on Epsilon, we follow YouTube mathematics content and include the most relevant videos that we find in Epsilon Stream. Part of the process involves the expertise of our content team, however other aspects are automated. For example, our system automatically tracks YouTube mathematics videos from dozens of channels. More on how we do this is in this blog post.

A by-product is that every month we update our estimate of the number of hours of mathematics watched on YouTube. This number typically lies in a range between 4 Million hours and 5 Million hours! That is a lot of math and shows that the world really appreciates the great content produced, and that is in English alone. If we were to count other languages the estimate would be bigger. For the month of November, there were 4.25 million hours of mathematics video views.

So back to the question: do mathematics videos age? Rephrased differently:

**Out of the 4.25 million hours watched how many were new? How many were from a year ago? How many were a few years old?**

To answer this we analyzed the data, considering the number of views per quarter and created the following:

As you can see, it is certainly not the case that most hours watched were from very recent videos. It is rather content from the past 5 years that contributes to most of the viewing time. With a slight leap of faith, this suggests the following:

**Like mathematics itself, YouTube mathematics videos also have the ability to stay relevant for long durations.**

Yes, mathematics has existed in human knowledge for thousands of years and YouTube is much younger. Still, within the world of YouTube videos we see that great content created half a decade ago, still remains relevant today. We believe much of this content will stay relevant and useful for many years to come. Thank you creators!

Do you have any insights from this data? Or maybe you have a specific question that you'd like to pose? let us know. You can also register with us to get further updates.