How do I allocate revenue using the As Incurred Accounting distribution by percentage?

Can I allocate revenue to 2 different accounts and activity types based upon a percentage?

When I look at the Accounting Rules page, I do not see the ability to have multiple credit rows based upon percentage.

Example,

100,000 in expense for an As Incurred Contract.

Would like to allocate the revenue to multiple revenue accounts based upon a percentage:

20% to revenue account "X"

76% to revenue account "y", activity "1"

4% to revenue account "y", activity "2"

Is this possible, and how would I do this?

Thanks,