I have searched online and while I found several link explaining how to get higher Chemistry, I didn't find any concrete example illustrating how the individual chemistry number below a player card is calculated.

Referring to the image: 

Notice this is a CM in CM location with all 4 red links. The player has club loyalty bonus but no manager bonus as can been seen here: 

I can't seem to figure out how this value of 4 is calculated. To my understanding, I have provided all needed information in the images.

Could someone explain how this value of 4 is calculated?

Thanks.