Seconded (@Chuck). I believe--just from my own observations--that as we lose more and more weight, our weight loss becomes logarithmic-- that is, that we continue to lose weight at a decreasing rate until we hit the 'ideal' weight for us. Which is why we so often hear about 'those stubborn last few pounds.' This is especially true (I think) if we consistently eat the same caloric load with the same macronutrient ratios. There is a basal metabolic rate that matches every caloric intake, so that each body size (coupled with activity level) requires its own caloric intake to maintain a steady weight. For example: say a 110 lb body at a moderate activity level requires 1800 cals/day to maintain a steady weight. If I weight 130 pounds and am eating 1800 cals/day, I can lose weight pretty quickly. But if I weight 114 pounds and am eating 1800 cals/day, I'll lose weight more slowly. And If I weight 110 lbs, then I won't (in theory) lose weight at all. This idea comes from my days of practicing conventional wisdom, however, so I'm not 100 percent positive it holds. Maintaining the same macronutrient ratios, I think, is key.
I think that we all have different equilibriums--different 'ideal' levels--too, but you'll find yours just like everyone else does. And if you find that you continue to lose weight lower than you want to, just increase your calories! Which (for me) has been the most fun step of all!