I hold a lease on office accommodation for a term which now has 7 years unexpired and pay to the freeholder a rent of $97,000 per month. I also pay to the freeholder $14,750 every 3 months as a service charge. My costs of occupation in addition to these payments are $23,000 per month. I could sub-let the offices at a fully inclusive rent of $200,000 per month. Similar leasehold interests have sold on a yield of 11.5%. What is the value of my leasehold interest?