I saw my last column grow up above 50%. What does each column represent?

The figures represent the % of the available space that has been used.

@itimpi what is different of each column?

11 minutes ago, tamito said:

@itimpi what is different of each column?

The first column is % used on flash, the second % used of log space and the last one % used within docker image.

On mine, the last bar is 71% and is showing an error in notifications. How do I determine what needs to be done with this?

 

So, of course... minutes later Dr Google helped me figure out that my pi-hole docker (log intensive) was the issue and resolution was provided via this post:
 

 

Edited January 7, 20197 yr by CowboyRedBeard

5 minutes ago, CowboyRedBeard said:

On mine, the last bar is 71% and is showing an error in notifications. How do I determine what needs to be done with this?

Go to Tools - Diagnostics and  attach the complete diagnostics zip file to your next post.

Also go to the Docker page, click the Container Size button, and post a screenshot.