Professor Philip Lane:

This is a big issue. It comes back to the regulator. The data we see as academics come with a lag. The unfortunate thing about the crisis was that the boom was relatively short. My broad narrative is that in 2002 and 2003, the start of it could have been tolerated. In 2004, things were maybe still okay. The question is when in 2005, which is the key year, does one call stop? There is a mix. People started talking about this in 2006. Even if the credit boom was towards its peak, there was a lot of time in 2006 and 2007 to say we were in trouble and to ask how we could get out of it at the least cost.