xplevel.2da

This file defines the amount of experience points required to gain the next level by creature with class from first column.
In BG2 ToB we have:
2DA V1.0
-1
           1          2          3          4          5          6          7          8          9          10         11         12         13         14         15         16         17         18         19         20         21         22         23         24         25         26         27         28         29         30         31         32         33         34         35         36         37         38         39         40         41         
MAGE       0          2500       5000       10000      20000      40000      60000      90000      135000     250000     375000     750000     1125000    1500000    1875000    2250000    2625000    3000000    3375000    3750000    4125000    4500000    4875000    5250000    5625000    6000000    6375000    6750000    7125000    7500000    7875000    8250000    8625000    9000000    9375000    9750000    10125000   10500000   10875000   11250000   13000000   
FIGHTER    0          2000       4000       8000       16000      32000      64000      125000     250000     500000     750000     1000000    1250000    1500000    1750000    2000000    2250000    2500000    2750000    3000000    3250000    3500000    3750000    4000000    4250000    4500000    4750000    5000000    5250000    5500000    5750000    6000000    6250000    6500000    6750000    7000000    7250000    7500000    7750000    8000000    8250000    
PALADIN    0          2250       4500       9000       18000      36000      75000      150000     300000     600000     900000     1200000    1500000    1800000    2100000    2400000    2700000    3000000    3300000    3600000    3900000    4200000    4500000    4800000    5100000    5400000    5700000    6000000    6300000    6600000    6900000    7200000    7500000    7800000    8100000    8400000    8700000    9000000    9300000    9600000    9900000    
RANGER     0          2250       4500       9000       18000      36000      75000      150000     300000     600000     900000     1200000    1500000    1800000    2100000    2400000    2700000    3000000    3300000    3600000    3900000    4200000    4500000    4800000    5100000    5400000    5700000    6000000    6300000    6600000    6900000    7200000    7500000    7800000    8100000    8400000    8700000    9000000    9300000    9600000    9900000    
CLERIC     0          1500       3000       6000       13000      27500      55000      110000     225000     450000     675000     900000     1125000    1350000    1575000    1800000    2025000    2250000    2475000    2700000    2925000    3150000    3375000    3600000    3825000    4050000    4275000    4500000    4725000    4950000    5175000    5400000    5625000    5850000    6075000    6300000    6525000    6750000    6975000    8000000    9000000    
DRUID      0          2000       4000       7500       12500      20000      35000      60000      90000      125000     200000     300000     750000     1500000    3000000    3150000    3300000    3450000    3600000    3750000    3900000    4150000    4400000    4700000    5000000    5500000    6000000    6500000    7000000    7500000    8000000    8500000    9000000    9500000    10000000   10500000   11000000   11500000   12000000   12500000   13000000   
THIEF      0          1250       2500       5000       10000      20000      40000      70000      110000     160000     220000     440000     660000     880000     1100000    1320000    1540000    1760000    1980000    2200000    2420000    2640000    2860000    3080000    3300000    3520000    3740000    3960000    4180000    4400000    4620000    4840000    5060000    5280000    5500000    5720000    5940000    6160000    6380000    8000000    9000000    
BARD       0          1250       2500       5000       10000      20000      40000      70000      110000     160000     220000     440000     660000     880000     1100000    1320000    1540000    1760000    1980000    2200000    2420000    2640000    2860000    3080000    3300000    3520000    3740000    3960000    4180000    4400000    4620000    4840000    5060000    5280000    5500000    5720000    5940000    6160000    6380000    8000000    9000000    
SORCERER   0          2500       5000       10000      20000      40000      60000      90000      135000     250000     375000     750000     1125000    1500000    1875000    2250000    2625000    3000000    3375000    3750000    4125000    4500000    4875000    5250000    5625000    6000000    6375000    6750000    7125000    7500000    7875000    8250000    8625000    9000000    9375000    9750000    10125000   10500000   10875000   11250000   13000000   
MONK       0          1500       3000       6000       13000      27500      55000      110000     225000     450000     675000     900000     1125000    1350000    1575000    1800000    2025000    2250000    2475000    2700000    2925000    3150000    3375000    3600000    3825000    4050000    4275000    4500000    4725000    4950000    5175000    5400000    5625000    5850000    6075000    6300000    6525000    6750000    6975000    8000000    9000000    
where:
Numbers in the first row of table determine level of creature.
Names in the first column are class identifiers. The rest columns have assigned xp values required to reach them by creature. One have to remember that it will affect only main classes, so entering kits identifiers will not give possibility to make separate level progression table for it.
Of course one could add more levels with defined experience values.