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.
1 Many universities have a fiscal year that ends during the summer, both to align the fiscal year with the school year, and because the school is normally less busy during the summer months.  The Federal government's fiscal year ends on September 30th of each year.