Of course people metabolize drugs at different rates than others, including what the long term dosage gas been for the patient (matters a lot) but here is what the WHO says about withdrawal rate: "Stopping Klonopin With Tapering"
The best way to successfully quit Klonopin is to follow a slow tapering schedule. Tapering, which means gradually reducing your dose over time, is also the best way of preventing severe withdrawal symptoms.
It’s tempting to want to quit cold turkey as soon as you find the motivation or desire to do so, but it’s in your best interest to resist this temptation. In fact, the longer you draw out your Klonopin taper, the less likely you are to experience any withdrawal symptoms at all.

Tapering your Klonopin dose is a way of tricking your body into thinking it’s not in withdrawal. It is not an exact science, which means your tapering schedule should be updated as you go along. You will need to work closely with a physician who can adjust your dose every few days or weeks, as necessary.
Tapering Schedule
The ideal duration of your taper will depend on several factors, including your starting dose and primary goals. Studies in primary care settings have found that a gradual taper over at least 10 weeks is most successful. 6 Some people continue their taper for a year or more.
There is no universal tapering rate. The research suggests that generally speaking, slower tapers are more successful. 10 If you are doing a slow taper, your physician will only reduce your dose every two or three weeks, and the reductions will be small. People taking high doses of benzodiazepines may start with a quicker taper and slow down once a lower dose has been achieved.

If your withdrawal symptoms become too much to handle, your healthcare provider can slow down the taper and even increase your dose. The dose reductions are so small that you may not even notice them after the first couple of weeks.
at a dosage of 2 mg per day, the practical withdrawal dosage rate could still be in the 10 day time frame, per my own personal experience. At much higher dosages than 2 mg, well, it's up to the individual and his/her doctor and how the patient feels in terms of tolerable anxiety level and sleep quality. Again, melatonin and doxylamine succinate can easily offset the sleep issues as one withdraws from clonazepam, in my unprofessional but personal opinion. I'm a fan of Ambien (zolpidem) but some doctors put the fear of God into the patient over nightmares and bizarre sleep walking episodes which has happened only in a very few cases. I never experienced any of that with zolpidem, which I took for years. Good luck!