Here's the "royalty calculator" many of you are asking about.  Here's the link  http://www.pagaslease.com/calculator_natural_gas_royalty_form.php 

 

Put your total acreage in line 1

Put a 640 acres unit in line 2

Put our 20% royalty in line 3

Put 4 dollars in line 4

Put 4 Mmcf in line 5

Hit calculate button

 

You can try different outcomes by changing the numbers in line 4 and 5.

Line 4 will increase when gas prices rise

Line 5 will increase if more gas is produced in the well.  The numbers we are hearing in PA are above 4 Mcf