To find the value decrease per month, we need to divide the decrease in value by the number of months.
The decrease in value is $2,500, and the number of months is 6.
Value decrease per month = decrease in value / number of months
Value decrease per month = $2,500 / 6
Value decrease per month ≈ $416.67
Therefore, the value decreases by approximately $416.67 per month.