Anonymous is incorrect. This is not a total number of installations. What is it, the number of weekly users (people actively use the extension), and this is calculated weekly.
If you want to see the daily number of people installing the extension , you can see this on the latest statistics page:

You can go to this page from the developer toolbar by clicking "Statistics":

Unfortunately, Google Chrome does not allow you to see the total number of people who installed the extension.
However, I personally came up with a way to know myself:
1) When a user installs the extension, he opens a php page on my server (only once, only for initial installation), which is a php page that I immediately redirect to another page (I redirect it to the welcome page), but to this php page when visiting tablets 1 for every time the page opens.
2) On the second javascript page on my server, he collects these tags and adds them, displaying them in a good format so that I can see and control the number of installations.
You can make it even more complex by updating the javascript page with a new code for each version so you can see how much is installed for each version or even how many are installed every day. It depends on how much time you want to spend on creating javascript (and on the programming level).
Yes, my method is quite complicated and it took a lot of time writing php and javascript code. However, this is the only way.
Here's what my tracking page looks like:

As you can see, this does not mean anything, because only I will ever see it (I’m even protected by the password of the page), but it allows me to easily track my settings at any time.