The answer is not in months, can't remember the last time I have, and if I did, or do, I will repent, be forgiven and do it no more... As I said in a few other threads, God knows EVERYTHING about us, even our hairs are numbered.. He knows your heart better then your own mother 100x over... If your really sorry, you won't do whatever it was again,
we want to remain sinless, we don't know the day or the hour, when we will be snatched out of the earth, so I would say if you have sinned, repent with a sincere heart, and be blameless .. If your intentions are pure, and sincere, He knows us, you are covered through Jesus and the blood He shed for us. We are again blameless and sinless.. Stay that way
Must add, each day is a new day, new battles, it's a daily fight.. Care about today, tomorrow holds enough trouble of its own.