Student accommodation firm Unite Group saw an increase in the net asset value (NAV) of its UNITE UK Student Accommodation Fund (USAF) in the first quarter of 2011.The NAV as at 31 March 2011 was £0.822 per unit, reflecting an increase of 1.7% during the first quarter of 2011 (31 December 2010: £0.808 per unit).Almost half (0.8 percentage points) of the gain was accounted for by movement in swap rate values, while a similar amount was caused by movement in property values.The fund's property portfolio, comprising 21,697 beds in 64 properties across 20 UK markets, was independently valued at £1.237bn.Valuation yields remained stable during the quarter at 6.67% (31 December 2010 6.67%). In line with previous years, the group expects to recognise the majority of the annual rental growth in the next two quarterly valuations as reservations for the forthcoming academic year progress."We expect to deliver total rental growth of 3-4% over the year in line with previous guidance particularly given that reservations for the USAF portfolio for the forthcoming academic year are already at 60%, ahead of the 57% level achieved at the same time last year," said Unite's chief financial officer, Joe Lister. ---jh