Calories in chicken breast - so much discrepency

Hi,

I used the site a few years back and lost 20kg and got to my goal weight (haven't been on for a few years). My wife just started using it to try lose some weight and I have been helping her log her food. I have found a lot of the foods now are really poorly quality controlled (i.e. the amount of calories for what sounds like the same staple ingredient is wildly different), I don't remember this being such a case when I used the site.

One in particular I want to know what other people use, is chicken breast.
I checked MFP and googled a few sites and when normalised (to 100g of chicken breast, skinless) I had about 3 people saying 100g = 105calories, about 5 saying 100g = 150-170calorie and 2 saying 100g = 200calories.

What do people use?