Asylum seekers are allowed to submit more than one request for asylum. For second and subsequent requests, the authorities establish whether new facts or circumstances have arisen. Sometimes, there is a reason to reconsider a request for asylum, even if no  new facts have come up. This is the case, for example, if the policy with respect to which countries are safe and which countries are not safe is changed. The number of second and subsequent requests for asylum is not available for all years.
Since 2007, the Immigration and Naturalisation Service is able to distinguish between first and subsequent requests. Prior to 2007, this was not possible; the number of asylum seekers was counted, not the number of asylum requests.
Figures over 2012 are provisional, figures over 2013 are definite.