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Subtraction Assignment Operator (-=)

Subtraction Assignment Operator (-=) (JavaScript)


Subtracts the value of an expression from the value of a variable and assigns the result to the variable.

result -= expression


Any numeric variable.


Any numeric expression.

Using the -= operator is exactly the same as doing the following:

result = result – expression


Supported in the following document modes: Quirks, Internet Explorer 6 standards, Internet Explorer 7 standards, Internet Explorer 8 standards, Internet Explorer 9 standards, Internet Explorer 10 standards, Internet Explorer 11 standards. Also supported in Store apps (Windows 8 and Windows Phone 8.1). See Version Information.

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