How much do union members earn in France?

Below a sample of the distribution of union members household's income deciles, as was reported in the European Social Survey 2008 (http://ess.nsd.uib.no/ess/round4/download.html). In a nuthshell: about 30% of unions members have a Household's total net income superior to 3301€ per month, among which about 15% earn more than 4101€ per month. Those who earn less than 1,200 € per month represent less than 10% of total union members.

For reference, the specific question was: "Si vous additionnez toutes les sources de revenus NETS de votre foyer, quelle lettre correspond le mieux au revenu de votre foyer. Si vous ne connaissez pas le chiffre exact, veuillez donner une approximation. Utilisez la partie de la carte que vous connaissez le mieux." and the specific possible income brackets:

1 A : <950 € per month

2 B : 951 to 1200 € per month

3 C : 1201 to 1500 € per month

4 D : 1501 to 1750 € per month

5 E : 1751 to 2000 € per month

6 F : 2001 to 2400 € per month

7 G : 2401 to 2800 € per month

8 H : 2801 to 3300 € per month

9 I : 3301 to 4100 € per month

10 J : >4101 € per month
12 [nsp]
The way I arrived at this figure is by filtering the French ESS data and restricting to those who are current union members and then computing the distribution fo income deciles responses for that sub-samples.