How do I format numbers such that they appear like below:

On selecting the "," icon, format the numbers in this way 100 to become
100.00 and if it is negative then (100.00).
Likewise on selecting the "$" icon then display the number in this way 100
to become $100.00 and if it is negative then $(100.00).

The location of the dollar sign should line up down the column irrespective
of the length of the amount. I don't know why Excel doesn't do this by
default.

How do I then get Excel to always do this formatting by default.

Cheers
Mark