How much do you spend to heat S&B over the winter. Update

We heat with wood and only use the oil furnace when we are gone which is about 2 months in the fall and then another few months after New Years. We have 175 gal tank ( about $700 to fill ) and it will all most always make it 2 months. When we are away for short trips in the summer we leave the heat off. 1700 square ft, no storm windows, no storm doors, built in 1790 and we try to keep it looking like it did then. We use about 1 1/2 cord of wood a month when we are home.