With the US Dollar continuing to weaken against other currencies are google using this to skim of earnings from non-US AdSense users?

As a UK resident, my website is set up for UK visitors and UK advertisers, nearly all of these advertisers will be operating their AdWords accounts using budgets set using UK Sterling.

The fact they are competing against similar advertisers means the weakness of the US Dollar has little, if any effect on click pricing and daily budgets.

In other words, they are still paying Google the same amount in sterling, irrespective of the exchange rates.

This means when the exchange rate was 1 - 1.80 every £100 an advertiser spent related to $180.00 to Google.

With an exchange rate now of 1 - 2.10 every £100 an advertiser spends relates to $210.00 to google.

With this established it should mean that UK AdSense earners who are targeting UK advertisers should be seing a rise in US Dollar income in proportion to the exchange rates.

To sum up, assuming click rates etc. are consistent as the US Dollar weakens, UK based AdSense users targeting the UK market should see their US Dollar earnings rising at the same rate as exchange rates, meaning their Sterling rates remain consistent.

The question is, Are UK AdSense users seing this rise, or are google creaming it off hoping that nobody picks up on this?