According to the U.S. Census, population shift has occurred for the following reasons:
Spurred in part by growth of the energy sector, some metropolitan and micropolitan statistical areas in North Dakota and west Texas are now experiencing rapid population gains, while growth has slowed or halted for some formerly fast-growing areas in the South and West.
What you immediately notice are the dark green shaded areas (representing 3+ percent growth), many of which that were, of course, where the height of the madness was occurring during the real estate boom. Some of these areas were the southwest states and especially California (generally anywhere east of the San Andreas Fault). As well as selected areas in southern states, and even a few high-growth inland areas that saw a tremendous ramp up during the early to mid-2000s such as Idaho.
The last ten seconds of the video shows a contra trend, practically wiping out growth area by area in the same manner that it appeared ten years prior. Corresponding to the quote above regarding the impetus for the current migration in recent years, you see 3+ percent growth in North Dakota as well as the current popularity of Texas. Another very interesting shift is from the north western, Reno area of Nevada to the north eastern area of the same state. What was driving that growth?
At the risk of sounding a bit like Pudd’nhead Wilson for pouring over such things, additional data sets and customizable maps for metropolitan and micropolitan statistical areas can be found here, the interactive map here.