How can I loop row by row?

So I have Model Data and Survey Data. I would to check error with iteration formula as following Excel below.

First iteration, I have to check error by subtracting data model 1 2 3 4 5 6 with data survey 1 2 3 4 5 6, and i calculate the error. And i find the error is 479

i=1 RMS = model(1)-survey(1)

Second iteration, I check error by subrtacting data model 2 3 4 5 6 7 with data survey 1 2 3 4 5 6, and i calculate the error. I find the error is 158

i=2 RMS = model(2)-survey(1)

Iteration will stop after last data model - last data survey (in fifth iteration).

i=5 RMS = model(5)-survey(1)

Thanks before

[darova]

I want to help you but don't know how

Do you have any ideas?

[Anita Fitriani]

My idea just

RMS(m,n) = model(m,n) - survey(m+1,n)

[darova]

Do you know how for loop works?