I have seen on bounty that like example:
Facebook campaign
500-1999 friends- 1 Stake per week
Is that 1 coin per week?
No its not 1 coin. Steak means it depends on how many people join the campaign. For example there are 100 of you in the facebook campaign. The total coins allocated for bounty is 100,000 Xcoin and 20% is for the facebook bounty, then 20,000 divide it by 100 people. So you receive a total of 200 Xcoins
Lets make it clear here:
Facebook bounty 20% of 100,000 = 20,000
Total participants 100
20,000 / 100 = 200 Xcoins