If the loop is in another loop, allowing you to "call it", you could add a shift register that is initialized by the value from the last call, and then just increment the SR (add the "i" to it). This would imply the outer loop has a SR as well to hold the last "call's" value. It would be initialized with a zero. If the loop is in a subvi then this would be a good use of the "LabVIEW2 style global" or as it is also known, the "functional global". These (the lv2 global, etc.) have been described in many places on the NI site.
Putnam Monroe
PutnamCertified LabVIEW Developer
Senior Test Engineer North Shore Technology, Inc.
Currently using LV 2012-LabVIEW 2018, RT8.5

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