Shaman · Elemental Combat · tier 2 · from level 15

Reverberation

Rank 5/5

Reduces the cooldown of your Shock spells by 1.0 sec.

Doesn't change the damage or healing of any Shaman spell.

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.