All About Margins Economics 71a Spring 2007 Extra
Margin Requirements Margins on longs Calculation Maintenance Margins on shorts
Margins on Longs
Example Buy 100 shares at $10 share, 0.75 margin Total value = = (1000-borrowed)/1000 Borrowed = 250 Price falls to $5 share Total value = 500 margin = ( )/500 = 0.50
Maintenance Margin As prices fall, broker investors are worse off Broker worries about whether they can pay off loans Maintenance margin = margin where broker forces investor to come up with more money Hitting this is known as a “margin call”
Example Buy 100 shares at $10 share, 0.75 margin Total value = = (1000-borrowed)/1000 Borrowed = 250 Maintenance margin = =(p* )/p*100 Solve for p, p =