I used this very page. It is impossible to understand, to the best of my effort. At the very least, it is ambiguous on some things. I could not follow it.
Here's the full process, to my understanding:
1. Find the number of votes per seat (called the "general indicator"). Add up every vote for every list that passed the electoral threshold, then divide that number by 120.
2. Divide each list's vote total by the general indicator. Remove any decimals. This gives you the pre-surplus seat count of all the lists.
3. Parties with surplus agreements are now paired up and their votes and seats are combined for the purpose of the allocation formula. The remaining seats are allocated one at a time based on who has the biggest number for the following equation:
Number of votes for a party / (seats currently allocated to that party + 1)
4. When all 120 seats are awarded, take any seats that have been awarded to surplus agreement partners and divide them between the parties in that agreement, using the same formula as above.
