Please be aware that National Grid are currently experiencing difficulties with the Market Information areas of the website (Prevailing View, Report Explorer and Data Item Explorer). This is being looked into as a matter of extreme urgency.
The data in the above sections of the website is currently available in the "Direct Links" area of the Information Exchange Website - http://www.nationalgrid.com/uk/Gas/Data/help/mipi_add_doc/IE3DirectLinks.
National Grid would like to apologise for the inconvenience caused by these issues.