I think you also have to set a constraint at the Supply side (graph 1) where the amount of likes does not exceed your current average likes (assuming fb friends number is not significantly different after 1 year)
We also have to consider the limitation that not possible for all people to see your new photo hence losing potential likes. There is also exception rule as to whether you are good looking at all. An unattractive picture of you is not going to increase your likes no matter what you do- thats a sad truth unfortunately.
I think you also have to set a constraint at the Supply side (graph 1) where the amount of likes does not exceed your current average likes (assuming fb friends number is not significantly different after 1 year)
We also have to consider the limitation that not possible for all people to see your new photo hence losing potential likes. There is also exception rule as to whether you are good looking at all. An unattractive picture of you is not going to increase your likes no matter what you do- thats a sad truth unfortunately.