As you have seen today. The market has tanked by 20% in a day. If you were a restaurant owner and made $100 today. You would now be having $80 instead of $100

As you have seen today. The market has tanked by 20% in a day. If you were a restaurant owner and made $100 today. You would now be having $80 instead of $100 — which might be your entire profit margin.