(ShareCast News) - Real estate investment trust McKay Securities expected to up its full year rental income thanks to new lettings and a rise in occupancy.The company said it expected its contracted rental income to lift from £20.5m last year to about £30m this year.McKay reported a 7.8% rise in open market lettings for a combined contracted rent of £0.9m per year.The company also said it had a high tenant retention rate of 77.8%."Market conditions across the South East and London remain positive."The shortage in supply of good quality business space reported on 27th May 2015 in the Year End results, combined with stable levels of occupier demand, continue to generate growth in rental values." Shares in McKay securities were untraded at 0435 BST at 250.25p