Fully loaded boat goes up to 12,5kn on code0 and mainsail

Yesterday we did a 90nm passage from Martinique to St. Vincent. Boat is fully loaded as we are going into 14d. quarantine. Lots of food, bottled water, beer, wine, full water tanks - 900L, full diesel tanks - 450L + 80L for genset. And of course all the spares and toys as usual for livaboards. And still on a nice breeze of 18kn and 120-130TWA we are averaging 9kn of boat speed with occasional 12kn down some small waves.