My nutritional analysis that I ran is different than yours in the books. Why is that?

I use caloriecount.com and an analysis tool I paid for to calculate; with the cookbooks, we also randomly do "quality control" by picking recipes at random, and running them through a third site (self or livestrong) to make sure they are the same or within a few calories of each other. Unless we use the same program and input them exact same brands, there will be some discrepancy since each brand has slightly different nutrition values and most calculators use different brands or their "Generic" value, which varies from program to program. Even doing something like 1 apple with 1/4 tsp cinnamon comes up with different values in each calculator, for example. Please note that we also do not count optional ingredients (which would likely explain the difference in the muffins) This is the best we can do - we can't guarantee 100% accuracy and for those needing to be very strict about their calories, they should input everything in their calculator, with their specific brands.