14/02/2010 0000000065465700000000000000000000000000000000000000000000000000

2009        1.00
30/12/2009  1.18   +18%
11/01/2010  1.31   +11%
25/01/2010  1.34    +2%
04/02/2010  1.82   +36%
14/02/2010  2.53   +39%

Another big jump in difficulty yesterday from 1.82 times to 2.53 times, a 39% increase since 10 days ago.  It was 10 days apart not 14 because more nodes joined and generated the 2016 blocks in less time.