That's my first post here and I'm new so hello everyone
I've checked it lately because I was interested, data below is however for the bitcoinmarket.com, not mtgox.
2010-05-04 0.000233477876802472
2010-05-19 0.000384088499942779
2010-05-29 0.000269870554617762
2010-06-24 0.000260244937104219
2010-07-05 0.000234030032854582
2010-07-13 0.000351431332017243
2010-07-16 0.000259993085755703
2010-07-26 0.00020473911841001
2010-08-05 0.000162894147688258
2010-08-15 0.000119388745040818
2010-09-28 4.70170684416307e-05
2010-10-12 5.58769421072858e-05
2010-10-21 4.28101750108482e-05
2010-10-30 4.56054331263679e-05
2010-11-09 5.9519168140414e-05
2010-11-18 4.0775321482557e-05
2010-12-09 1.79562523916729e-05
2010-12-21 1.79506410875391e-05
2011-01-02 1.83965325437386e-05
2011-01-15 2.1694745353151e-05
The higher the value, the more profitable it is to mine.