The only three I had memorized.... I'd have to go back and look.
Every country defines a housing start differently. Australia and the United States define it as when the excavation starts on site. That counts as a housing start. In the U.K., it is when they start pouring the foundation. It's in between. In Canada, we define it as when that foundation reaches ground level.
These distinctions didn't used to matter all that much back when Canada was mostly building single detached homes, because the timeline from when you started digging the hole to when you poured the foundation and the foundation reached grade was usually a matter of weeks. Oftentimes, that was all happening in the same month anyway.
Now we're moving to more complex high-rise apartments, most of which have underground parking. The timeline from when you start digging the hole to when the foundation reaches grade can be up to about 18 months or so different.