That is only the base rate at or below $30 per barrel. At $92.5/bbl it is 50%. From there it rises another 0.1% for every $1 increase.
http://www.commonwealthnorth.org/documents_cwnorth/Final%20OITS%20Report%203-15-11.pdf
Page 6,p> Keep in mind this is after the royalties are first paid. The companies also pay property taxes if the property is used for oil/gas. No other industry in Alaska has to pay state property taxes.
Then the Feds add their corporate taxes.
So may I presume no one disputes that Gov. Palin raised taxes from 22.5 percent to 25 percent on a major American industry based in Alaska?