It's just another monster reference, but has three nice enhancements:
1) Nicer rendering of certain data. Experience is shown as 4 numbers: the amount of experience per 4 | 3 | 2 | 1 characters. [ No need for dividing all the figures by number of characters. ] All "dice" (money drops + attack damage values) are given in the "dice" form (4d5+40) as well as the "range" form (44-60).

2) Using some Grayface's formulae, it gives the meaning to the resistance values. Apart from their real values there are also brackets containing the average reduction of damage for that resistance (something like 30 (67 %), meaning that you can expect the given type of damage to be reduced to 67 % on the average).

3) Using some more Grayface's formulae, it gives chance-to-hit tables for every monster in the game. There are two tables, one for hero hitting a monster (you look up the nearest Attack Bonus value and get the chance to hit for it), another for monster hitting a hero (the same thing for Armor Class value). A quick look in this table can show you whether your current characters stand a chance against any particular foe by checking your chances to hit them, their chances to hit you, and how much of the damage you see on your character screen actually makes it to them.