Welcome to the community!
So this concept (and the example you have given) will get you along way (hopefully!) to start understand 'How Tableau Thinks', and in particular how Table Calculations work.
So to do this we use the RANK function. This is a Table Calculation, which means that the results aren't 'hardcoded' into the data, but are dependent on the level of detail in your Viz, and how you set it up. I've worked up and example from superstore
So first I create my Rank function on Sales
I've then also made it discrete, so I can display it as a column in the Table (you don't need to do this to make it work btw). When we bring this field into the Viz, Tableau will set it up in a default fashion (kind of a 'best guess'). For Table Calculations there are 2 concepts;
Addressing and Partitioning. Addressing means, what should I run this RANK function over (in our case we want this to be Customer, as these are who we want to rank). Partitioning means, restart my rank every x.
So I go into the 'Edit Table Calculation' (you can find this by right clicking on the measure), and goto 'advanced'. In here I've set this up as follows
So we are saying 'Rank (Descending) the customers on SUM of Sales, and restart the Rank every month'
Once we have this, we can drag the Rank to filter shelf, and select numbers 1-10...and voila
Hope that helps, and makes sense, but please post back if not as there are some great blogs on the subject of Table Calculations I can point you to.
Ranking Example.twbx 351.2 KB
Thank you for your help! I used your instructions to figure it out. Still working on understanding it all, but I'm starting to piece it together. I'd love to see your blog recommendations if you have them handy.
In terms of Table Calculations (as well as the On-Demand Videos Tableau provide) I'd also check out this great Think Data Thursday Webinar
I'd also check out this blog
there are links that will take you to a series of Blogs/Posts going from beginner to Zen in Table Calcs