Size is one of the properties for conveying data that is shared with many other crafts.
Typically, the final project (or piece) is intended to be a particular size overall. Rather than adapting one data point as one textile unit (stitch, row, etc.), it’s generally better to convert the data to percentages and then map that onto the textile units. For instance, if each row of the back of a knit sweater pattern is 150 stitches, and you have three data values that are 33%, 50%, and 17%, you could represent it by 50, 75, and 25 stitches in the colors representing those data values, respectively. Or there are 50 rows that make up the back of the sweater, you could do rows (all 150 stitches) in a single solid color, and have 16 rows in the first color, 25 rows in the second color, and 9 in the third.