Create index for cell ranges

[MILTINO]

Greetings dear friends, please can you help me in this
In a book I have a Fja BD that contains a list of data from B21:D35501 which are recorded on Sheet 2 in templates of 72 rows each, a total of 500 templates
What I want is to create an index in the BD column G sheet like this in the example I have done manually but it is too much to do for 500 templates
Thank you attached example

 

[Skovgaard]

I think you forgot to attach your example

/Skovgaard

 

[MILTINO]

it does not allow me to send indicates too big

 

[ValuationMan]

In other words, it's not clear what you're asking for. Can you uploaded a screenshot or a mini-sheet to help show what you're asking for? You could also scale down your workbook.