DOLLAR:
Converts a number to text, using the $ (dollar) currency format
The DOLLAR function converts a number to text using currency format, with the decimals rounded to the specified place. The format used is $#,##0.00_);($#,##0.00).
DOLLAR takes
1 required argument and
1 optional argument:
Syntax: DOLLAR(number,
[decimals])
Using the DOLLAR function:
The arguments for the DOLLAR function are:
Argument

Required?

Description

number 
Required 
A number, a reference to a cell containing a number, or a formula that evaluates to a number. 
decimals 
Optional 
The number of digits to the right of the decimal point. If decimals is negative, number is rounded to the left of the decimal point. If you omit decimals, it is assumed to be 2. 
One very important detail:
• The major difference between formatting a cell that contains a number by using a command
and formatting a number directly with the DOLLAR function is that DOLLAR converts its
result to text. A number formatted with the Format Cells dialog box is still a number. You can continue to use numbers formatted with DOLLAR in formulas,
because Excel converts numbers entered as text values to numbers when it calculates. 
The DOLLAR function converts a number to text using currency format, with the decimals rounded to the specified place.