Hello folks.
Finally I'm running successful campaigns in Facebook. This forum is rocks. 
(Special thanks to Caurmen, Zeno and Kokofai for this achieve
)
So, I've got an overall 137% ROI. Broad campaign at Facebook.
My question is: when is it time to stop a segment?
I have pause 18-21 age segment because I thought I was just starting to lose money. Frequency cap and cpc was going up and at each hour was losing more.
Take a look at this graph, is it time to stop or continue? Or is it too early?
Anyone to share own experiences? Thx guys!

Has this campaign been running for only one day and you are already profitable? If so you should consider yourself extremely lucky and be very happy because this is GREAT! 137% ROI is not something you want to cut if you've seen some success already but we don't have much more information other then the graph. How long has this campaign been running and if you are in the green (profitable) with it, I would try to tweak it some more and maybe try a few different angles/demographics on Facebook just to see.
I'm no expert in Facebook but I do know that If I had a profitable camp on it I would keep tweaking and testing it. You have a winner but only if its been running for at least a week I would say. One day of data is really not enough to even remotely start asking yourself if its good or not. You need much more data then just one days worth - of course all depending on the ad budget your spending lol 
Hi David. I think wasn't lucky
I ran some tests before with 18-21 segment.
That segment was profitable for 2 days.
So, today, profit for that one was oscilation positive and negative at each hour, but more negative so i stopped that one for now. Was losing money on that.
I realised i started losing money when frequency got 1.8 and click's price got 0.11 (before was 0.6)
But others segments are profitable since I they started them today.
I would let it run for a week as you said David. Really thanks.
When you're at very low spends the hour-to-hour profitability will always fluctuate.
It's important to collect data over many days and drive more traffic so that hourly P/L is more reliable (e.g. making at least 5 conversions an hour).
By the way, that's strange, because the segment had 360.000 profiles.
I reached 200.000 and the frequency got 1.8
So, 120.000 were persons who did not access facebook on these days?
Are there any way to minimize the frequency cap in facebook?
My gut feeling would be that you'll need about 2-3 times that much data minimum in order to reliably pinpoint day-by-day trends. How many days was it gathered over? Obviously, for day-by-day data like this you'll want a couple of weeks of data to be sure it wasn't just that there was nothing good on TV that night 
How many days was it gathered over?
Hi Caurmen. I just have 2 days of data.
Great point: "be sure it wasn't just that there was nothing good on TV that night".
I'll let it run for days then and will bring more data to the thread.
Really thanks Caurmen.
You should run a campaign with a proper amount of volume before ending it. Say 5-7x the offers payout.
Also a campaign should never die in 1-2 days. Facebook does sometimes have shorter life spans, but 1-2 days is tooooo short!
But the offer payout is just $1 dollar stackman. I've already get that.
What's bother me is that crazy cpc, yesterday was 0.06. Now It's 15 cents in ocpm mode.