What is accruals/defferals: Accruals/deferrals handle the correct, time-based distribution of revenue
or expenses from interest in the Transaction Manager. At the end of each month accruals will show amount of interest that you can get earned, and this amount will be shown in reports. But you cant get this amount of money because of agreement.
Typical example of accruals/defferals: you have deposit from 15.03.2015 till 15.06.2015. You receive interests every month: on 15th.
But at every end of the month you need to prepare reports. It means you need to show accruals/defferal. At the end of month you have to show distribution of revenue. As soon as you start accruals, you will see on 30(31) revenue from 15th till 30 (31). And in most cases you will reset accruals on the 1st of each month. Hope you understand what i wrote.
So in your case you don't have accruals, because you are receiving interests at the end of month. You are earning revenue from the beggining of month till the end of month. You will show it in your reports as revenue and as money your received.
If you use checkmark "Incl." then system takes another period to calculate accruals, i described this earlier.