Cannot Sum Summed cells

[globewandrer]

I have been using excel for 20 years and never had this problem before. I do these calculations 1x per month for the past 5 years, this is the first time I've had trouble

I have summed various cells. I now need to sum those cells. I cannot sum the summed cells. How can I sum the cells that have already been summed?

The value of C157 is 1.

The value of C158, is the sum of C2:C157 = 108

I now want to sum C157:C158, but I get a value of 1, it should be 109.

How do I get it to see the summed value in cell C157

Thanks!

[#2]

Update:

Sheet 2 is working correctly and SUM is working like normal, but Sheet 1 is not. Sheet 2 is an exact copy of Sheet 1, so.......?

[#3]

@globewandrer 

The SUBTOTAL function ignores cells that also contain a SUBTOTAL formula.

If you would sum C157 and C158, you would count C157 twice, since C158 is the sum of C2 to C157.

[#4]

@Hans Vogelaar 

I guess my issue then is Subtotal, which is what Excel is default using instead of Sum.  I select "Sum", but it uses "Subtotal" instead. Thanks for replying.