The duration of commercial property leases has hit their lowest level on record, according to new figures. The British Property Federation's (BPF) Annual Lease Review has discovered that the average length of commercial lettings has fallen to five years, from 5.9 years in 2008/9. The last year has also seen growth in the employment of break clauses on lease contracts, as well as the continued use of rent-free periods in order to entice new tenants, according to the analysis of 91,000 tenancies. The organisation said: "Lease lengths have halved in the period since the Conservative Party last formed a Government in the 1990s, and stand at less than a quarter of the 21-year average in 1991.” It said 72% of new leases signed in 2009/10 were of five years or less, and 90% for 10 years or less. The proportion of leases with a break clause increased to 29.4%, compared to 28.2% a year earlier. The average rent-free period in 2009/10 was 10 months, with the average in the office market at 14.5 months, as tenants were able to negotiate attractive deals.