In the US , the number one hit on my birthday was " With Or Without You " by U2 , which is rather cool because it 's quite possibly my favourite U2 song .
Question: What can be inferred about song rankings from the author 's specification of where the U2 song was the number one hit at the time ?
The answer to the above question:


That the number one hit at any given time is most likely not the same in every part of the world .