Development Securities, co-owner of the Manchester Evening News Arena, the largest indoor venue in Europe, said its net assets value reduced by 1% to £329.6m from £333.1m at 31 December 2010.
Within its interim results on Thursday morning, the property development and investment company said its net assets per share was 269p, from 290p in June 2010.
DevSec reported a pre-tax loss of £1.3m for the six months to 30 June 2011, compared to a profit of £0.8m for the equivalent period last year.
Net debt was £128.5m at June this year compared to £107.3m in the same period in 2010.
In June this year, DevSec refinanced the MEN Arena after securing £23.75m with Yorkshire Bank. The bank is lending alongside Lloyds Bank Corporate Markets, which provided £47.5m in April last year to finance the acquisition of the Arena by DevSec and private equity house Patron Capital Partners.
The developer and investors said 14 projects were added to the group in the year to date, taking the total to 43 acquisitions since July 2009, with progress on most projects on or ahead of plan. However, DevSec continues to seek large-scale development projects in central London.
As well as co-owning the 21,000-seat MEN arena in Manchester, DevSecs' other interests around the North West include the new Booths supermarket development in Hale Barns.
David Jenkins, chairman of DevSecs, said: "The majority of our development activity has focussed on London, albeit mostly on the outer districts rather than the core central locations.
"At Hale Barns in Manchester, we obtained planning consent for our retail and residential scheme and secured Booths as the anchor for a 30,000 sq ft food store."
Elsewhere, DevSec is positive about bringing a further 280 new homes to Broughton, near Chester, in Flintshire.
Jenkins added: "At our Broughton residential site near Chester, our Appeal against non-determination by the local authority will be heard before an Appeal Hearing on 28th September 2011 and we are pleased to note that the local authority is now publicly supporting our proposals subject to resolution of the Section 106 Agreement. Once the Inspector has prepared his report, it will be placed before a Welsh Assembly Government Minister who will make the final decision. Accordingly, we are now hopeful of reaching the end of this long and complicated planning process to provide circa 280 housing units into a market where supply is constrained."