How to copy formula without column row numbers adjusting?

Hi Again, I have 6500 rows to work on and I was trying to copy the formula alll the way down, but the formula automatically adjusting it's number ex:

The underlined are changing
A14 =INDEX(DETAILS!E7:E6540,MATCH(I14,DETAILS!K7:K1471))
A15 =INDEX(DETAILS!E8:E6541,MATCH(I15,DETAILS!K8:K1472))
A16 =INDEX(DETAILS!E9:E6542,MATCH(I16,DETAILS!K9:K1473))
A17 =INDEX(DETAILS!E10:E6543,MATCH(I17,DETAILS!K10:K1474))

I want it to be copied this way:
where the only one changing is the I column
A14 =INDEX(DETAILS!E7:E6540,MATCH(I14,DETAILS!K7:K1471))
A15 =INDEX(DETAILS!E7:E6540,MATCH(I15,DETAILS!K7:K1471))
A16 =INDEX(DETAILS!E7:E6540,MATCH(I16,DETAILS!K7:K1471))
A17 =INDEX(DETAILS!E7:E6540,MATCH(I17,DETAILS!K7:K1471))

I tried to copy it one by one, but for three days I'm only at the 300th rows, I have 6200 rows to work on.

please help!