At united healthcare $UNH (-6.94%) went down quite a bit today. However, I got a fright when I looked at my portfolio and saw that it was down 17%. If I click on the value, however, we only see -7%, which looks better again.
How can this be? I recently had something similar with Porsche AG $P911 (+0.35%) and customer service wanted to take a look at it, but after a few inquiries I didn't hear anything more about it.
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PS: the two screenshots were taken a few seconds apart.
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