Mathematical formula (subtraction) of views in drupal?

Question

Drupal

Colleagues, tell me plz!
By means of a view, I display a list of new materials (name and tags). I need to display the tags not in a literal value, but in a numerical value, i.e. amount! In this case, subtract 1 (one) from the result (quantity).
The question is how to subtract one from the result?
An example is the toaster itself, on the main page of which the material and the main tag are displayed, and the number of additional tags is indicated in quantitative terms (For example: google + 2 MORE).
I assume that you need to replace the output with a php formula, but what should the formula itself be?

Answer 1

Can be implemented with Computed Field and Views PHP
Or handles via hook_views_data_alter