The difference between the cost price and the retail price of merchandise. Markup may be expressed in dollars or as a percent. If stated as a percent, it may be based on either cost price or retail price. Most retailers base markup on retail price.
Measure the entire shape of a curved shower rod if this is the style you have. Expect the measured width to be approximately 6 inches more than a standard curtain rod. Purchase a shower curtain with a 72-inch width, if available, to compensate for the additional width. If necessary, a 70-inch curtain width works as well. This is because the rods curve inward at the edges, making for an overall smaller width measurement.
The Size Regardless of what size shower curtain you're making, add on 16 inches in length and 8 inches in width for the hem. After you put together two panels to create a panel that is 88 inches long (72 inches plus 16 for the hem) and 80 inches wide (72 inches wide plus 8 inches for the hem) it's time to sew!