Little help? Burn meter seems to be underestimating...

I was looking at my burn meter, specifically at the smaller total estimate of the calories I'll burn by the end of the day. It seems to be reading a bit off..??

At the start of today, the total estimate read: 1680. Then during the day, I added 1000 additional calories burnt off through exercise. My total estimate now reads 2448.

What am I missing....anyone? Have my basic math skills degenerated THAT MUCH?!! Lame.

Now, I think I'm more worried about my ability to do simple calculations than wondering about the complex alchemy of the burn meter.

Thanks, in advance.

The 1680 number is your total estimated calorie burn for that day if you stay at the activity level that you had chosen when you set up your profile on the site. (Sedentary, Lightly Active, Active, etc.) If you add 1000 cals of exercise, it subtracts the calories that you WOULD have burned if you'd sat there doing nothing. Example: you would burn 60 cals an hour sitting, but if you'd jogged all that time and burned 400, realistically, only 340 cals should be added to your estimated total for the day.

 That's my take on how the burn meter works. If I explained it horribly, don't hesitate to ask again. ^^;

No, that is a big help! I hadn't realized the burn meter goes ahead and subtracts the cals I would have burned had I just been sitting there. That makes good sense that it would factor that in. 

Ouch, I have less wiggle room than I thought for the day!! :)