I'm not sure this kind of thing would be too helpful, because people lose at all different rates for all different reasons - age, gender, metabolic rate, starting BMI, activity level, whether or not they lost weight prior to surgery, how closely they stick to their plan, etc. I was a slow loser from day 1, which some very insensitive medical resident pointed out to me - showing me a chart of where "most" patients are at point X, and pointing out how far behind the curve I was. It really bothered me because I stuck to my program about 99% of the time that whole first year. What else was I supposed to do? Change the fact I was female and post-menopausal and had a pokey metabolism rate? Luckily, I resolved to prove the jerk wrong and ended up losing 100% of my excess weight, blowing pretty much all the other patients in my co-hort out of the water. But I could have responded the other way - thinking I was a failure, and thinking that he'd just confirmed it.
as long as follow your program and your weight trends downward (allowing for the occasional stall along the way), you're good.