Self storage firm Big Yellow returned to the black in the first half of the year and resumed its dividend payment as occupancy levels continue to pick up.The group reported a pre-tax profit of £8.6m for the six months ended 30 September 2010 compared to a pre-tax loss of £3.4m the year earlier. Revenue for the period increased to £31.1m from £29.2m before. Big Yellow, which operates 61 stores, is set to open a further nine which will provide a further 4.4m sq ft of self storage space when completed.Chairman Nicholas Vetch commented, "Big Yellow continues to make steady progress in its key ambition of increasing occupancy across its store portfolio."He added, "The business is experiencing the usual seasonal slowdown, but as in previous years, we look forward to an improvement in demand from early 2011 as we enter our more buoyant spring and summer trading periods."An interim dividend of 4p has been offered compared to no payment the same period last year.