Reports the total level of available industrial floor space across Great Britain to have increased to 21.241 million square metres at June 2007, with the highest increases in central England. This represents a rise of 4.5% (910,000 square metres ) since December 2006. Availability in new buildings increased 14.6% since December 2006. At June 2007, it was 2.604 million square metres across Great Britain. This means that new floor space accounted for 12.3% of total availability at June 2007. Available floor space in large units (of 10,000 square metres and over) was also up, with a rise of 6.2% (340,000 square metres ) to 5.852 million square metres . Speculative development under construction across Great Britain has also increased since the last survey in March 2007, to 1,445,096 square metres across 131 schemes. This represents an 18% increase in floor space under development in July 2007 compared with six months earlier.