From Ed:

As it says at the bottom of every stats page on the ND system, we show a generic click price for the first 24-48 hours after a click is made. This is because Google does not show realtime earnings stats for any of their partners and we are no different. However, we are the only PPC company to show you exactly what you earn with Google rather than a generic value based on 'historical data'. Our default PPC for the US is $0.11, so all US clicks are valued at that until we receive the real earnings data from Google. This default value is actually less than half our average PPC for the US across our whole system. We have chosen a conservative default PPC so that the cases where the PPC appears to 'drop' after the update is kept to a minimum. Unfortunately, if Google does then pay us less than $0.11 for the clicks, then the update amount will be lower than the amount originally shown.

As I've stressed before, this is simply updating a default amount, not reducing the earnings shown in your account. If you want to PM or email me your account ID, we'd be happy to have a look into whether we can get the PPC up on the account.