From 1979, the first European elections by direct universal suffrage, to 2019, the last reference for this election, the left lost 19 points and has fallen, since 2014, below the mark of 35% of votes cast. In four decades of presidential elections the disintegration of the left has been of the same magnitude.
The government parties which had made the heyday of the French left under the Fifth Republic, and particularly the PS, are in decline. The collapse of the PS within a left in sharp decline is linked to this.