How to Autofill columns with Sum and Indirect formula

[Sunshine8790]

I have a workbook with 13 sheets. 12 of them are all set up like calendars, one for each month of the year.
The other one is a summary page.
It is the summary page I need help on.

So this is a small excerpt of my summary page table below:
The formulas in row 2 are all correct.
However, I need to be able to autofill the formulas in each column down without changing the first cell reference.
So for example in Column C, I want to keep the formula in C2 as:

=SUM(INDIRECT($C$1&"!"&"$AH12"))

But I want to be able to autofill it down (we're talking a few hundred rows I don't want to have to manually re-type the code) to keep the first reference to "C1" but change the 2nd cell reference by 1 increment.
So in cell C3, I want the formula to change from AH12 to AH13:

=SUM(INDIRECT($C$1&"!"&"$AH13"))

In cell C4, I want the same thing, keep the C1 reference, but change the AH reference to 14, etc, etc.

And of course I need the same logic for the other columns. To keep the first cell reference, but change the 2nd by 1 each time.

Any help?

PTO FY23 Tracker.xlsx
	B	C	D	E	F	G	H	I	J	K	L	M	N
1	Name/Month	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
2	Name 1	0	0	0	0	0	0	0	0	0	0	0	0
3	Name 2	0	0	0	0	0	0	0	0	0	0	0	0
4	Name 3	0	0	0	0	0	0	0	0	0	0	0	0
5	Name 4	0	0	0	0	0	0	0	0	0	0	0	0
6	Name 5	0	0	0	0	0	0	0	0	0	0	0	0
7	Name 6	0	0	0	0	0	0	0	0	0	0	0	0
FY23 PTO Summary

Cell Formulas
Range	Formula
C2	C2	=SUM(INDIRECT($C$1&"!"&"$AH12"))
D2:D7	D2	=SUM(INDIRECT($D$1&"!"&"AE12"))
E2:E7	E2	=SUM(INDIRECT($E$1&"!"&"AH12"))
F2:F7	F2	=SUM(INDIRECT($F$1&"!"&"AG12"))
G2:G7	G2	=SUM(INDIRECT($G$1&"!"&"AH12"))
H2:H7	H2	=SUM(INDIRECT($H$1&"!"&"AH12"))
I2:I7	I2	=SUM(INDIRECT($I$1&"!"&"AG12"))
J2:J7	J2	=SUM(INDIRECT($J$1&"!"&"AH12"))
K2:K7	K2	=SUM(INDIRECT($K$1&"!"&"AG12"))
L2:L7	L2	=SUM(INDIRECT($L$1&"!"&"AH12"))
M2:M7	M2	=SUM(INDIRECT($M$1&"!"&"AG12"))
N2:N7	N2	=SUM(INDIRECT($N$1&"!"&"AH12"))
C3:C7	C3	=SUM(INDIRECT($C$1&"!"&"AH13"))

 

[Tetra201]

Try placing the following formula in cell C2 and drag-copying it down as needed:

=INDIRECT($C$1&"!AH"&ROW()-ROW($C$2)+12)