How many calories should a 23 year old woman who weighs 141 lbs and is 5 feet 6 inches eat in a day if she would like to lose 20 pounds?

I too am 23, I am 5'3'' and weighed 142 at my highest. Right now I am at 136 and would also like to be around that 115 to 120 level. I started using an application on my iphone called Lose It. It tells me that my daily calorie budget is 1,696 and that I will loose a half a pound per week. Its pretty hard but I'm trying it! Hope this helps a little bit! Good luck with everything!