I totally agree with petitfromage - not only that an airline which never had an accident, is less likely to encountern one in the future, it is also q question of the statistic itself.
If one calcultes deaths / paxmile, certain airlines will always be on the top, because they have longer routes - just compare the average distance flown on domestic flights in Australia with a much smaller country like Switzerland.
In some cases it would be much more serious to calcultae victims / movement, which would favour another group of airlines.
And not forget: It 's not only the airlines fault / merit - what can an airlie do if ATC (for example, also right for every other party envolved) is useless?
Regards, Bernhard