The legislative elections of June 12 and 19 will send 577 elected members to the National Assembly. So many elections that take place in constituencies whose contours have remained unchanged for three elections. If, during the votes in the Hemicycle, the deputies represent the nation and vote equally, with one vote each, the territories in which they were elected are less equal. The legislative electoral division results in very disparate constituencies in terms of area, population, but also income, unemployment or age pyramid, as pointed out by the National Institute of Statistics and Economic Studies (Insee), which published its “Portraits of legislative constituencies” in early May.
The last constituency redistribution, which took place in 2010, was based “on demographic criteria” ; according to the principle of equality before the vote, each deputy should be elected in a territory with an equivalent share of the population. According to the INSEE publication at the beginning of May, each of the 539 districts of metropolitan France has an average of 120,000 inhabitants. The vast majority (85%) are around this range, more or less 20%, but there are variations ranging almost from simple to triple between the 2e constituency of Cantal (62,753 inhabitants) and the 5e Loire-Atlantique (167,177 inhabitants). This disparity is pushed to the extreme with Saint-Pierre-et-Miquelon, a territory of 5,974 inhabitants.
A gap between the population and the registered
However, to be elected, more than the total population, it is the number of registered voters that matters to the candidates. Depending on the demographic particularities of each constituency, and primarily the proportion of minors and foreigners (who do not have the right to vote in legislative elections), the number of registered voters is more or less close to that of the total population. It can thus be up to 25 times higher from one constituency to another.
The proportion of registered voters in relation to the total population is therefore indicative of disparities. The people likely to elect their deputy represent less than half of the inhabitants in 17 constituencies, where there are many young people and immigrants: this is the case in Mayotte and Guyana, but also in the Paris region (in six constituencies Seine-Saint-Denis, three from Val-de-Marne, two from Essonne), Marseille and Strasbourg. Conversely, in many constituencies on the oceanic and Mediterranean coast but also overseas, those registered represent more than 80% of the population.
The 12.5% threshold, strong disparities depending on the number of voters
As a result of these disparities, the amount of voters that each candidate will have to convince varies considerably. To remain in the second round of legislative elections, in the event of a triangular election, candidates must obtain the votes of at least 12.5% of registered voters in their constituency, regardless of the level of participation in the election. For all the reasons mentioned above, this minimum number of voters varies from 1 to 47: it takes 16,851 votes to remain in the second round in the 3e constituency of Vendée, but only 631 in Saint-Pierre-et-Miquelon, and 29,738 for the French in North America.
Constituencies with very diverse faces
Beyond the number of inhabitants, voter profiles also vary from one constituency to another. By retaining the average age, the poverty rate and the urban or rural character of the territory, the following graph shows how the 550 districts for which this data are available are distributed, according to INSEE. Each dot represents a constituency. The higher it is, the poorer the constituency; the further to the left, the younger its population. Urban constituencies are colored in purple, rural ones in green. This scatter plot shows that most rural ridings tend to be older on average and less affected by poverty.
By combining the share of retirees in the population, the median household income and the vote cast in the first round of the last presidential election, it is possible to observe how the geographical division of the constituencies strongly varies the type of electorate to be conquered. . In the following graph, a point which tends to be located at the bottom right refers to ridings where retirees are, in proportion, more numerous than the average and where the median standard of living (which cuts the population in two) is place below the national average.
Three fairly distinct groups are formed within the constituencies according to the vote cast in the first round of the presidential election: Marine Le Pen and Jean-Luc Mélenchon thus came out on top in the constituencies where the median income is lower than the national average with, for difference, the weight of retirees in the population. Emmanuel Macron has done well in higher income areas.
To further explore the characteristics of each district, we offer a map of six indicators provided by INSEE which highlight the disparities.