Percentage to roll back in.

To adwords, overture, etc.

[Powdork]

I'm wondering if anyone would like to share their statistics of how much they roll back into getting new traffic, whether it be a % or what.
I now have a sales person and I'm thinking 40% for her, 40% for me and 20% back into the site, whether that be for advertising or adwords or overture. I am taking care of the overhead (adsense, with a tidy sum left over). It is a local travel/recreation directory and we are the only two participants.
Any ideas or pointers welcome.

[TheGuyAboveYou]

I think this would depend on wether you need to use money for daily personal spending or wether you can continually invest it. It is a hard question because it seems it also depends on ROI. If I double my money for every dollar I put in then I would spend as much as I can. To me it has never been about how much I spend its how much I make.
I will spend 1k a day if I make 1k a day. A lot of internet growth seems to be exponential and not linear. I personally put most all of it back in when possible. The exponential growth is really seen if your business has repeat customers then the value of rolling money back in really comes back over time. I usually write code in a program called Matlab once I know conversion rates etc. and it tells me what to put back in.

Not sure if this helps but it is a hard question :).

[Powdork]

Thanks,
I'm wondering if this is an ok amount (20%). At least at first I will need my percentage for personal daily spending. I want to include the number as part of the contract with her so their are no questions. I guess some or a large part of it would depend on when the PPC programs reach levelr of diminishing marginal returns since my epc would be relatively constant.
I guess it is a tough question, which is probably why I'm here.