Just follow the link through the global average mean and then to the actual dataset that underlies the monthly graph (the third graph on the page)- click on the "Data File".

Also, below is the direct link to the data .... and you can see that the December 2007 value is 0.114 - the last time it was this cool was January '97.

http://hadobs.metoffice.com/hadsst2/diagnostics/global/nh+sh/monthly