Self storage firm Big Yellow grew annualised store revenue by 7% during the third quarter and has made a good start to 2011.Revenue rose to £58.9m at its 51 wholly owned stores in the last three months of 2010, up from £55.1m the year before. Total store revenue rose to £15m from £14m, but is down from £15.5m at the end of September."Against a backdrop of mortgage approvals significantly below their ten year average, and a slowly improving economy, we are encouraged by the increase in occupancy of the wholly owned portfolio from 54% to 58% of capacity over the calendar year," boss James Gibson said. "January has started positively with reservations growing in line with last year, and we look forward to growing occupancy, revenue and cash flow over our seasonally stronger spring and summer trading period."