The increase in UK public sector net borrowing in the past year, plotted in figure 1, has been in part a result of the decline in economic activity, and also a consequence of the change in housing and financial market transactions. The former is predictable with every 1 per cent decline in output below trend producing a decline in net revenues of of between one third and three fifths of a per cent of GDP depending upon the reason for the decline in output. The loss from the decline in asset-related revenues is harder to judge, but the April 2009 budget suggested that revenue losses might be more than 1 per cent of GDP.