So just how much do the French neighbours earn?

It may sound like an invasion of privacy, but the link on the geoportail.gouv.fr site opens to an interactive map where you can search your (or another) area to see average earnings.

You fill in your commune number or the address and a map comes up squared off into 200m x 200m coloured segments for the level of average earnings per person.

The levels range from grey, for €7,000 to €17,300 a year each, through yellow for €21,600 to €23,800 and up to red for those earning €31,500 to €100,000.

Levels with diagonal grey bars do not give values, for privacy, as resident numbers are low.

The map also gives the numbers living in each segment – so businesses can work out if it is worthwhile investing in a new shop or unit and if there will be enough trade.