Shaman · Enhancement · tier 2 · from level 15

Mental Dexterity

+16.3 Attack

3/3 · level 60 · per cast · and 1 more

Mental Dexterity 123

Rank 3/3

Increases your Attack Power by an amount equal to 100% of your Intellect.

Attack +12.8% +16.3 Stormstrike +11.9% +14.5

Averages, counting crits and misses, for a level 60 Shaman with a typical weapon and no other gear or buffs, against a target your level. Worked out from the game's own data, the same way as the Foresight addon.