countif, indirect, autofill, help

[DELETED LINE AFTER MOD TOLD ME IT SERVED "NO PURPOSE"]

I have a large number of spreadsheets and one summary sheet at the beginning.
I need to reference another sheet, use countif to calculate a specific number.
I want/need autofill to increase, incrementally the criteria in the formula.

For instance: =COUNTIF('92040'!$I:$I, "6")
[SAME RUDE MOD WANTED TO KNOW WHAT THE "6" WAS.]

The formula is counting how many homes were sold in a specific zip code during which month. The zipcode is the '92040'. the "6" is the month of June.
The zipcode won't change, but the "6" needs to become a "7" and so on....

Otherwise I have to adjust every formula by hand.

I need the "6" to go up to "7" and more with autofill, so I can just drag it across the column and have it fill in.

I CANNOT FIGURE OUT A WAY TO DO THIS! And I don't want to correct each formula by hand.

[DELETED LINE AFTER MOD TOLD ME IT SERVED "NO PURPOSE"]

One way...

=COUNTIF('92040'!$I:$I, COLUMNS($A1:F1))

COLUMNS($A1:F1) evaluates to 6. As you drag copy the formula across the row it will increment like:

COLUMNS($A1:F1) = 6
COLUMNS($A1:G1) = 7
COLUMNS($A1:H1) = 8
COLUMNS($A1:I1) = 9
etc
etc