How to count sum based on actual year

Hey,

I have a problem and I don’t know how to find a solution.

Let’s assume that we have two tables:

  1. Invoices
  2. Clients

These two tables are linked - one client has many invoices

Now in the Clients table I would like to have calucalted field, which counts the sum of all invoices from actual year.

How to achieve this?