CURRENT_PERIOD_INDEX

Current period index returns the value of the period that is selected.

Example

Consider the scenario where you want to calculate the Balance due for a loan taken for $40000.

Periods	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
Loan amount	40000	35000	30000	25000	21000	17000	14000	11000	8000	5000	3000	1000
Amount paid	5000	5000	5000	4000	4000	3000	3000	3000	3000	2000	2000	1000

To achieve this the following formula should be written in the [Balance due] node:

[Loan amount]-[Amount paid].GET(CURRENT_PERIOD_INDEX)

Balance due	35000	30000	25000	21000	17000	14000	11000	8000	5000	3000	1000	0

Explanation

As we used the current period index for Amount paid it will take Feb's value to subtract with Feb's loan amount, Mar's value to subtract with Mar's loan amount and so on.