Keep in mind too that Glassdoor is only as good as the people posting on there. The person that posted the $72k could have posted something higher or lower than what they really make, and there's no corroboration. They could have also been posting for the same position but in a different locality for the position. For example, the area I live in has average wages almost exactly 50% of national wages. So, if I was working for a company that had offices in NYC and in the city I'm in, the NYC post for my position would likely be more than the $72k but the local post for my position would definitely be less than the $72k. An average of the locations might be $72k but a candidate who applied in NYC and used Glassdoor to request a salary based on the average of my post and my NYC counterpart's post would would be short-selling himself, whereas a candidate locally who asked for $72k would be dismissed with a laugh.
Therefore, I would be looking more at what the position generally pays for your area and what your other options are. Robert Half's salary guide is a good starting point to get a national figure for the position, then something like https://quickfacts.census.gov/ can be useful to look up your locality and determine how your wages are likely to relate to national wages. Armed with this information, you know about what the position “should” pay you. The second part of the equation is what other options do you have? If this is the first offer in 5 months of job-hunting, and your alternative is prolonged unemployment, then your acceptable range is going to be lower than if you're currently at a job making $70k and you're willing to hold out for a position that pays at or above market for the title and work.
All that being said…try to avoid stating what pay you want or expect and try to get them to throw out a number first. Then ask for what seems like a reasonable difference from that number. Only state it in a “I need xxx or I won't take the job” manner if you really mean it. We have chosen not to offer a job to certain candidates based on them giving the impression that they wouldn't take it for less than xxx and we couldn't offer that much (or didn't want to), so we never even offered the position. You want to negotiate the best starting pay you can, but not exclude yourself by asking for something ridiculous (for example, based on the data you've relayed, I would feel like asking for $82k would be ridiculous…but if they offer $79k to start with, then with that new data, $82k would be reasonable to ask for).