Duplicate Record With Formula

Hi everyone,

I've just begun with quickbase and i need help with this problem:

When creating a new sale record classified with a specific sale type, i would want to automatically create a new record containing the same values of the first one but with the amount multiplied by '-1'.

Example:

Record ID:         Costumer     Sale Type         Inovice nº  Amount
1                            John              CON                  32               500$
Record ID:         Costumer     Sale Type         Inovice nº  Amount
2                           John              CON                  32               -500$

It's possible?

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Pedro Sampaio
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