Okay, supposing I wanted to make a skirt I designed. How would I figure out how much yardage I needed? For example: I mapped out a skirt that is 18" at the waist (sits low on hips), 30" at the hem and 20" long. I multiplied 20x30 (thinking it was easier to figure the area of a rectangle than a trapazoid and I could somehow find a use for extra yarn

) and got 600. Then divided it by 36 to get yardage instead of inches. Got 16.66. There is no way I can make the front of a skirt with 17 yards of yarn. Gauge would be 4-5 sts per inch. What am I doing wrong?