National Australia Bank chief executive Andrew Irvine is the second most experienced boss of a big four bank. He’s also been in the job for just 15 months.

The share price gains posted by NAB and Australia’s other banks in recent times have been so stunning – NAB’s stock has risen 54 per cent in the past two years, and Commonwealth Bank has dragged the ASX 200 bank index up almost 20 per cent in the past 12 months – that you can almost forget just how much change we’ve had at the top.