Do you really believe there is no controversy over oil taxes in North Dakota?  A sixth grader can do the math if the sixth grader has the information. However, if you do the math on one set of numbers and find out there are errors in those numbers you have the wrong answer to the actual problem.  

Here is a link to a company specializing in auditing oil company royalty reports: http://www.gelbercorp.com/royalty-auditing/    They would not be in business if they were not finding oil company's using creative reporting.