Using a formula to allocate to categories in split transaction

Here's what I see under Help/split transactions/percentages:

Memorize and use a split transaction with percentages

In the register or Write Checks window, enter the date and payee, as usual. Enter the total amount of the transaction in the Payment or Deposit field. Tab to the Category field, and click Split. Enter the percentages in the Amount column, select a category and, optionally, enter a memo for each item. The first line shows the total amount of the transaction. Select it and type a number followed by the percent (%) sign. Then click Next. For example, type 60 percent on the first line and 40 percent on the second line. When you enter a percentage and then move to the next field, Quicken calculates the dollar amount. Click OK to close the Split Transaction window. Click the Edit button, and choose Memorize payee. Click Yes to confirm that you want to memorize the payee with percentages. Click OK again to memorize the transaction. Click Enter.

Note To use a split transaction with percentages Scroll to the bottom of the register or Write Checks window, and select the new transaction line. In the Payee field, enter the payee associated with the split transaction you want to use, and press the TAB key. Enter the total dollar amount when Quicken asks for it. Click OK. Click Enter. Quicken enters the transaction for the amount you specify, with the dollar amount split according to the percentages stored for the memorized payee.

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