It starts at around 10 when you're born, unless your mom drank a lot. It shoots up to 25 'till 6, then plummets to the negatives and stays in "limbo" there until 18. Then it can continue to drop or skyrocket. Usually the dropping part happens. At around 25, it has returned to normal, and it rises to about 75. Then it stays, unless you're actually fun. then it stays at 25 untill you die.