What does "spud date" mean in oil drilling?

In oil drilling, the spud date is when a machine capable of reaching total depth begins drilling a new well. This process is also known as spudding in.

Before a company can begin extracting oil from a well, they first need to drill a surface hole and fill it with concrete. This is done to protect the groundwater around the hole from becoming contaminated during the extraction process. The drilling rig is equipped with the main drill bit and begins drilling toward the final depth of the well.

The spud date is extremely important to investors. It helps them estimate the effectiveness of a drilling company, as shorter cycles generally indicate a more efficient process.