The above graph is courtesy of Bloomberg. The top half shows the spread between the UK 3 month LIBOR (Orange) and the OIS 3 month rate (white). The difference between the two rates is that LIBOR is artificially created by bankers, whereas the OIS rate is established by the market. The second half of the graph displays the spread between the two rates. Historically speaking the two rates track each other almost identically, as they should if bankers are submitting honest quotes. However, during the credit crunch the spread between these two rates widened to historical highs as LIBOR quickly decreased (meaning borrowing was cheaper) whereas the OIS rate only dropped to that level after the credit crunch was over. No graph shows the LIBOR scandal and its manipulation better than this one in my opinion.