Undercutting their own argument with misleading statistics

There is a hugely emotive piece in the Herald today which is trying to justify higher wages for cleaners etc on the basis of the difference between their wages and the effective hourly rate paid to professionals.  Without wanting to get into any discussion about the validity of the argument, all of my sympathy disappears (again) when I saw the table presented below:
Hourly rates
$489.47   Top 44 CEOs
$206.37   Auckland City CEO David Rankin (library owner)
$91.35     Finance directors
$48.08+   Law partners
$21.29     Average wage
$10.95     Cissy Alone (librarycleaner)
$10.25     Legal minimum wage

For a start - who knows a CEO that only works 40 hours a week?  Even the ones I know that only put in 50-60 hours a week in the office tend to take work home.  Hard to take the library home to clean it there.
What would be wrong with calculating the above statistics on the basis of the number of hours that actually tend to get put in by salary employees?  The argument would still exist - and at least then it might be valid.

I'm also disturbed as to where the $21.29 average wage figure comes from - I'm pretty sure last time I checked the average wage wasn't $42,000 per year.  In fact I'm pretty sure the average employee income isn't that high....
Tags: NZ, New Zealand, minimum wage, misleading statistics, statistics