Adding a symbol

I am wondering if there is a way to add a symbol in the same place in multiple rows using a formula.

EX: 0010055C
0010260C
0010860C

I need to add a "-" (dash) after the first three digits, so it looks like this:
001-0055C
001-0260C
001-0860C

There are 1354 rows I need to do this in, so if there is a formula it would help out a lot!
Thank you.

Try a formula in an adjescent column

=REPLACE(A1,4,0,"-")

Jonmo1,

That works for one row, but is there a way to do multiple at a time?

I tried this formula:
=REPLACE(A2:A10,4,0,"-")

Once I typed the "A2" part of the formula I would drag the blue box that surrounds the cell down to add more rows. After the formula is done I would hit enter but only A2 would be how I need it.

Thanks for your help.

Just put the formula in one cell.
=REPLACE(A2,4,0,"-")

Then fill it down, the A2 will change to A3 then A4 as the formual is filled down.

It worked! Thank you so much for your help!

Great, glad to help.

Actually,

Now when I'm actually trying to replace the old column, without the dashes, with the new column, with the dashes, it won't let me because I'm deleting the building blocks for the formula that I used. So, if I delete column A and then paste the new column to column A it says "REF". Is there a way arround that?

Copy the column with the formulas
PasteSpecial-Values onto the original column
Delete the column with the formulas.

Wonderful. Thank you.