I would like to suggest that when I change my calorie count for a specific day or week that it does not then change my calorie count in the past too. For example: I changed my calorie count today to reduce it and it then reduced all my historical calorie counts going back to the day I started using this app. I need to see my history and the changes i've made. Now it appears i was over and under with my new calorie count in months past.
Can I suggest that only the day I change my calorie count and weight loss goal only feed from that day forward and not my history as well?

thank you.

Good idea, I've thought about this also!

Amen, this has been requested so many times. I'm guessing the programming to do this is too involved with all the other tweaks they are working on but this would be a fantastic option.

From the help section up top in the line with username and logout link

http://www.myfitnesspal.com/help/faq/270-can-i-change-my-calorie-goal-without-affecting-my-historical-entries

It's "not a simple fix" but on their to do list.