 On the Charturti day (4th day after new moon) of each month, the 'Sankashta Ganapathi Pooja' prayer is performed.Each ‘Vratha’ (strict fast) has a purpose and is explained to us by a story known as the ‘Vratha Katha’.This prayer offering has 13 Vratha Kathas, one for each month and the 13th story is for 'athika' (The Hindu calendar has one extra month every 4 years).