Fitbit inconsistency

Ambition00

I recently got a fibit one and I am finding that there are inconsistencies between the calories burned for the same amount of activity /steps taken for the day. For example:

VAM = very active minutes
CB = calories burned
Fl= floors climbed
St = steps

21,912 st
2415 CB
37 VAM
8.96 mi
9 fl

20126 st
2291 cb
24 vam
8.2 mi
16 fl

25,604 st
2561 cb
10.58 mi
33 vam
20 fl

24,277 st
2394 cb
10.51 mi
68 vam
34 fl

18738 st
2306 cb
7.57 mi
29 vam
27 fl

30914 st
2754 cb
12.88 mi
52 vam
17 fl

then yesterday 25285 st
2339 cb
10.62 mi
55 vam
94 fl

so thinking that it would be similar to the last time i had 25k plus steps I would burn close to 2500 cals i didn't and I event had more hills/steps yesterday. i guess i would expect that if the stats were close the calories burned should be roughly the same and so forth if the steps taken are close but the vam or the fl is higher that i would see a greater calorie burn. anyone know why mine is all over the chart? it makes it hard to gauge how many steps i need to take in order to be around a TDEE goal.