An early round of fireworks sparked by an upbeat manufacturing report led Wall Street to its biggest five-day gain in two years.

The Dow Jones industrial average rocketed nearly 170 points yesterday, capping a weeklong rally that saw most major indices enjoy at least a 5 percent spike starting the third quarter.

The Dow gained 648 points, or 5.4 percent, during its five-day run-up — it’s best week since July 2009.

The rally, which kicked off just ahead of the July 4th holiday when trading volumes tend to be light, was driven by a regional survey showing a better-than-expected pickup in manufacturing activity.