I'd like someone with expertise to analyze this data. Often blunt data like what's in this article can mislead outsiders. For example, how is the start defined

I'd like someone with expertise to analyze this data. Often blunt data like what's in this article can mislead outsiders. For example, how is the start defined? Maybe that's a technicality, depending on local permitting laws. Maybe post-construction legal or regulatory issues are involved. Maybe it's tied to weather or the ground. I'm just making up possilities - the point is, I have no idea myself.