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We won't mind a bit.
Not really sure about the figures being inflated by the drupal but may be because Joomla came into existence in 2005. I was experimented with Google Trends, and just had a look at the comparison between drupal and joomla, Joomla seems to be rising in popularity since its existence but clearly Drupal has been around for a longer time. May be that is the reason, just a idea!