It is a finished floor but in these old homes around here it could have been laid 50 years after the house was built and still be 75 years old. Common here during that time to even put plank sheathing on the inside walls and leave open studs to the outside covered with wood siding. That way the farmer had inside walls to get him going for 20-40 years until he had money to get them horse hair plastered. same with floors.
The old house we are in now I was pleasantly surprised when I opened a wall for an arch way to find the hardwood flooring continuous under it. Did have holes for wires but they were easy to plug.