1. HOW MANY CURTAIN WIDTHS? As most curtain/lining fabrics are 137cms wide we need to know how many curtain widths to use. Thus track width x 1.5 (Tab/Eyelet) or x 2 (Pencil Tape) or x 3 (pinch pleat) and then divide by fabric width 137cms. E.G. 200cms x 2 / 137cms = 2.919 (round this up to next whole number = 3 widths) 2. HOW MUCH FABRIC IN EACH WIDTH? Take your overall curtain drop, add 25cms for hems and divide by pattern repeat (if there is one). Thus 250cms + 25cms / 64cms = 4.29. Round up this answer to next whole number (5) and then multiply this figure by your pattern repeat. Thus 5 x 64cm = 320cms of fabric for each width. 3. FINALLY Multiply no of widths (3) x fabric required per width (320cms) to give total of fabric required = 960cms or 9.6 metres