I have been on a 12 week plateau....

I have been ranging between 176 and 180 since the end of Jan. I've been working out with weights doing the ball, taking 2.5 mile walks three times a week so when will this end?? I just don't get it I do think that I'm losing inchs,but I don't measure myself so I'm not sure, my clothes have been fitting a little better. How many Calories a day have you guys been eatting??? Sarah 264/176/160ish