On April 21st 2011 at 12:30GMT the Public Sector Net Borrowing data for March were released.
Previous value: 10.3B; Forecast: 19.3B
Public Sector Net Borrowing is the amount of money the government needs to allocate in order to finance various governmental programs. 
Any positive value of the index indicates the lack of such funds and vice versa. If, for example, the authorities try to solve the problem through emitting extra cash money, it obviously makes the national currency decline in value against foreign currencies. However, it should be noted that there are different ways of allocating the money.
For those who trade Forex any info on Public Sector Net Borrowing is important. Usually traders get ready for a decline in the country’s national currency rate (in this case - the British Pound) if the value is above zero.
The data are published in the middle of each month following the reporting one.
