I have a several rows of formulae that refer to a constant at the upper left
corner of the range of formulae. I use an absolute cell reference to refer
to the constant, and many relative relative references in rows of formulae.
I want to copy this range of work and paste it several rows below the
original. However, I want to use a different constant for the second range
of formulae. Since I used an absolute reference in my original work, the
pasted formulae still refer to my original constant. How can I make the
reference to the original constant be absolute, yet relative to each range of
formulae so I can change the constant each time I paste the range of
formulae? For example:

A1=7
B2=100, C2=B2+A$1
B3=105, C3=B3+A$1
B4=110, C4=B4+A$1

Now, copy this range A1:C4 and paste down at A15, now we have:

A15=7
B16=100, C16=B16+A$1
B17=105, C17=B17+A$1
B18=110, C18=B18+A$1

However, what I really wanted was for A$15 to be my new constant (so I could
change the number in that cell) for this new range of formulae. My actual
formulae are much more numerous and complicated that this and I am trying not
to have to go in and manually change each cell reference for the constant on
my new range. It seems like I need some kind of formula in my original
constant cell reference (A$1) that will allow it to change when it is pasted
elsewhere. I have tried INDIRECT and OFFSET, but can't come up with a way to
make them work. Many thanks in advance for your thoughts.