Honoring the other Π (PI), The Elegant Farmer celebrates National PI Day with a 3-day pie sale March 12-14 exclusively in the market. PI is the mathematic symbol that defines the value of the ratio of a circle's circumference to its diameter and the value of 3.14. The Elegant Farmer celebrates National PI Day with a 3-day pie sale March 12-14 exclusively in the market get $3.14 off any of our simply the best 8″ Pies Baked in a Paper Bag.