In CVP analysis, the contribution margin is the dollar amount remaining after deducting variable expenses from sales revenue. The unit contribution margin is the amount that each unit of sold product contributes. In this example, the unit contribution margin is $50 (price of $100 minus variable cost of $50).
Vision Problems in the U.S. estimated the population with glaucoma to be 2.7 million in 2010. This number is estimated to be 2.86 million in 2014, and will increase by nearly 50% to 4.3 million by 2032 and by more than 90% to 5.5 million by 2050.
1 It is uncommon below the age of 40 but this type of glaucoma affects one per cent of people aged over 40. About five per cent of people over the age of 65 have primary open angle glaucoma.  Your race: if you are of African origin you are more at risk of POAG.