Ubiquinol is much better absorbed than ubiquinone, so if you're taking ubiquinol (and you should be!), you won't need as large a dose. Some studies have indicated that ubiquinol is up to 8 times more bioavailable than regular (ubiquione) CoQ10.
Also, is the CoQ10 you're taking in an oil base? CoQ10 taken in an oil base is also said to be more bioavailable than other forms.
Important note: If in an oil base, make sure that it's not in a base of soy/soybean oil! Soy oil has been shown to cause genetic changes in the brain and shouldn't be taken or eaten for any reason.
I realize this doesn't actually answer your question, so let me say this: the more health issues you have, and especially if you're taking a statin drug, the higher the dose of CoQ10 you should take.
I don't really have any health issues, and I take 100 mg per day (Doctor's Best, which I get at either Vitacost or iHerb). Even though I don't have health issues, I'd take the Doctor's Best 100 mg dose twice a day (for 200 mg per day) if I could afford it.
I hope this helps.
edit: clarity