What is the combined numbers of the PSG attacking trio that shows the trio don't work together?

For an attacking trio consisting of the world's finest players, PSG numbers are nothing to write home about. Lionel Messi's arrival was expected to improve the productivity of the Ligue 1 attack but the Argentine has not been able to level up since joining.

Lionel Messi got his first goal in the league last match against Nantes, with just three goals in the Champions League, he has four goals and one assist across all competitions. 

Neymar Jr is having a really bad season, the Brazilian forward has just six goals in 13 matches across all competitions, he is yet to record a goal or an assist in the Champions League this season. 

Kylian Mbappe seems to be the one saving the attacking trio with his goals contributions so far this season, the France international has 21 goals across all competitions this season with two goals and five assists in the Champions League alone. The attacking trio has been poor in the final third.