calculating within transactions?

[hymie!]

Greetings.  Still a new user, learning all that gnucash can do for me.

Can gnucash do "spreadsheet"-style calculating within a transaction?

For example, my paycheck is divided into several deductions:
* Federal Tax
* State Tax
* Social Security
* Health Insurance
* Retirement Plan
* Net Pay

A few of these items (like my health insurance and retirement plan) are
not counted in my taxable income.  So the other side of my transaction is
divided into:
* Income:Salary:Taxable
* Income:Salary:Nontaxable

What I would like to do is automagically say
* Income:Salary:Nontaxable = Health Insurance + Retirement Plan
* Income:Salary:Taxable = (the sum of all entries) - Income.Salary.Taxable

Is this possible?

hymie!          http://www.smart.net/~hymowitz          hymie at lactose.smart.net
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