For each person? Really? Do you want to waste your tokens or not? Please clarify this and why you give 400$ each person? I would be thinking if that 400$ was calculated the airdrop so for example, there are 800 people who have registered in the website, then the calculated amount for the airdrop is $400, then for each person they will get $0.5 each. This calculated system is more good enough than you give them $400 valued in tokens for each person, it will give you enough pressure to the person who has registered to sell once your tokens hit an exchange and you can expect massive selloff for your tokens.