How much money should you tip the cleaning lady for Christmas?

Gratuities (tips) are 15% of the total you pay that person in a month. Example: If the cleaning lady comes twice a week at $25 each time she comes then you would pay her $30, but it would nice with all the work she does to round it off to $50 if you can financially do so (or any amount you wish to give.) You are actually giving a gift not a tip.