What percentage of all suicide attempts are carried out by people suffering from bipolar disorder?

Hi Sam 
Not sure anybody's calculated it that way, or at least not that I've ever seen.  Usually it's more like what percentage of patients with a given diagnosis commit suicide.  Viewed that way I've seen one statistic suggesting that bipolar II carries a bit more risk than bipolar I, which is close to but slightly greater than the risk for schizophrenia (to the extent that we can really tell the two apart, which is tricky).  These latter two are about the same at around 10% as "borderline personality disorder".  There is surely some percentage from PTSD and OCD, though lower.  So, adding all that up, I come up with around 50% due to bipolar disorder.  A probably related fact is that lithium has a very good track record in lowering suicide risk. 

Dr. Phelps