A GROUP of private investors who have paid £2.7 million for Shannon Business Park will earn an initial yield of 13.8 per cent on their investment. There is a rent roll of £405,000 from the park, which has five two-storey buildings with a total of 41,000 square feet and parking for 150 cars. One building is let to Woodchester on a long-term lease, two others are occupied by the Irish Aviation Authority on leases with break options and the other two are let to nine tenants on short-term leases. Because the buildings are located in the Shannon free airport industrial zone, licensed tenants qualify for 10 per cent corporation tax. The sale completes the disposal of Silvermines's property interests in Ireland.