how much walking is on paved roads?

Roads from Paris

I walked the Via Turonensis last year in May.
We followed - as closely as possible - the Confraternity of St James' "Paris to the Pyrenees" guide book.
I would say that 75% of the first 500kms walking from Paris was on tarred roads - some heavy traffic where you feel as though you are taking your life in youir hands! Further south, one starts to find Le Chemin de St Jacques 'camino like' paths. After Roncesvalles, I think only about 25% is on tarred roads although you usually have an alternative - tarred road or camino path. In heavy rain or bad weather we followed the route recommended to cyclists and that was on tarred roads.
Buen Camino,
Sil