The biggest factor in how many calories you burn per mile of walking is your weight rather than your speed. According to the research that produced these numbers, at a walking pace speed makes only a minor difference. You will burn more calories by walking more miles.
I believe the Army starts their fiscal year on 1st October and runs until 30 September.
When a fiscal year overlaps parts of two calendar years, it is actually the ending-year, not the starting-year, that applies. If the tax year ends on July 31, 2014, using your example, you would file using 2014 forms and rules by October 15 (the 15th day of the third month following close of a tax year) under IRS rules.