Ask HN: What's your LOC-to-Developer Ratio?

I work on a small but amazing development team that has been churning out high quality software for the past 6 years. We've added a few people and lost a few people to normal churn, but basically have written and now maintain close to 3 million lines of code (LOC) with 5 developers. (General break down is 1/2 million in Java, about 2 million in HTML/CSS/JS, and remaining in various XML configs, property files, and etc.)

We're trying to make a case that although we've been able to do a lot that we're well past the sanity point of LOC-to-dev ratio with each developer responsible for maintaining about 600K LOC.

I do realize that it's not a perfect science, but am curious to hear the ratio that you have on YOUR team and what breaking points you've identified in the past or thresholds that you're using to identify when to add people.

I also welcome other suggestions for alternative metrics than LOC that do a better job of showing load-per-developer and any benchmarks for what's reasonable. Thanks!