How have I done so? Part of the contract negotiations on a time and materials contract concerns the billing rates for the personnel who will perform on the contract. The government has a schedule of what it is willing to pay for certain domain expertise and levels of experience.

You have been down voted, but your observation is correct, and the parent comment is misleading as to rates. Source: I’m a government contractor and line manager.

I worked for government contractors for almost 15 years (until October 2016) and participated in proposal efforts ranging from $750k SBIRs to a $1B+ multi-year prime contract for a radar system. Every one had established billing rates for labor, based on the type of employee rendering the labor. How is this misleading?

It's misleading because, for experienced + well-qualified people, the upper ranges of the established rates are rather high, and therefore don't significantly constrain the hourly rates of those people.

So for instance, if, within a given discipline like "security", there are 6 experience levels (1 = fresh-out undergrad, 6 = most senior), and within those, 4 maturity levels (20th thru 80th percentile, say), then the 80th percentile of, say, level 5, will be a very high rate.

Because it's HN, and the comments above were referring to boutique security consultants ("top NSA specialists work[ing] for contractor firms"), I assumed that's who we're talking about. Cybersecurity, especially, has become a domain where institutional constraints have been lifted in the last few years - it requires less on-paper experience to get up to the "level 5" above.

On the other hand, and in agreement with your comment, the aggregate labor rate for a large contract (I'm sure $1B qualifies) could not be too out of whack with industry norms, and this would be a significant constraint on rates.