This file defines the influence of dexterity on characters actions, such as dodging missiles and AC bonuses.
The first row (titles of columns ) is filled by the names of actions.
The first column is filled by value of dexterity of character.
The other columns are filled by values for given dexterity.
The reaction value is unused, but it is displayed in the character sheet.
In BG2EE we have:

2DA V1.0
0
     REACTION MISSILE  AC
0    -20      -20      5
1    -6       -6       5
2    -4       -4       4
3    -3       -3       3
4    -2       -2       2
5    -1       -1       1
6    0        0        0
7    0        0        0
8    0        0        0
9    0        0        0
10   0        0        0
11   0        0        0
12   0        0        0
13   0        0        0
14   0        0        0
15   0        0        -1
16   1        1        -2
17   2        2        -3
18   2        2        -4
19   3        3        -4
20   3        3        -4
21   4        4        -5
22   4        4        -5
23   4        4        -5
24   5        5        -6
25   5        5        -6