This is the number commonly quoted. It's very much
in line with my experiences.

That must be related to overhead involved in dealing with unions, I
don't know because I've never had to deal with unions. I know my own
experience, including owning my own network engineering and software
dev firm for 12+ years, our burden rates were about 30% and that
included a full benefits package (vac, sick leave, insurance), 401K
match, employers share of FICA, unemployment cost and loss of
productivity for the few slackers we occasionally ended up with.

I suppose if I divided all of my other overhead per employee it would
be closer to 60%.

The consulting firms and supply chain/distribution firms I've worked
for in the past 8 years all ran with about a 30% burden rate as well.

It's interesting that your experience is so different.

Tillman