Found this study where they actually tried to measure the effects and impact of Bipolar on various subjects and their work (or ability to work)

"People experiencing bipolar disorder have a strong desire to maintain employment, and display high academic achievement compared with people with other forms of affective difficulties. AIMS: To explore the views of people with bipolar disorder (BD) about how their experiences of BD influences their employment, and how being in work can change their experience of BD."

The full article is HERE.