They've always had something similar to this, but this looks really good, and the timing is no coincidence... 
Wonder what Nebraska's secret is, and whether we're about to see a large migration there... 
The numbers are nice, but without any clarification of how the numbers are produced (and how those formulas are tweaked from administration to administration), they're really not all that useful.
For example: inflation. The consumerpriceindex (CPI) used to be based on one simple shoppingcart of goods that never changed ... as that cart went up in price, that's how we judged inflation.
Then, the government started using complicated formulas (when the government deliberately makes things too complicated for the average voter, you gotta wonder what they're up to), and voila! No inflation according to the formulas, lately.
Why would the government do this? Well, payments – welfare, social security, vet. benefits – are all tied to the CPI, so if they can manipulate the CPI so that it doesn't show inflation, then they don't have to raise payments.
That's just one example. Like I said, unless it shows more detail on how the number is reached (and how the current formula differs from, say, the 1999 formula), it's just not all that useful.
Unless you're a politician or journalist, that is ... then, well ... details are for geeks anyway, and your voters / readers won't know the difference until it's too late. 
The population graphs do not look consistent.
Here is a graph of states with high growth rates. google.com/publicdata?ds=uspop ...
It appears that Texas has the greatest slope and thus the highest growth rate. If USA is added to the graph it has an even steeper slope. It should not be steeper than all of its constituents. google.com/publicdata?ds=uspop ...
Texas vs USA: google.com/publicdata?ds=uspop ...

On review California may have a steeper average slope that Texas over the entire time span The USA slope is much steeper than each of them, which seems wrong. 
No, the US curve should be steeper than all the state curves because its slope is the sum of all the other slopes.
Say you add two linear equations 3x + 2 and 5x + 3. The resulting equation is 8x + 5, which has a steeper slope than both of the other equations.
Check the math here: walterzorn.com/grapher/grapher ... 
Trogdor: Not to get into a big econ debate here but... The CPI is a measure of the change of prices in a fixed basket of goods from a base year to the current year. It is imperfect in many ways. Lets say that in the economy there are only two products, red apples and green apples. And the CPI is based only on the prices of the red apples. If the price of red apples increases rapidly but the price of green apples stays the game and you like each type of apple equally you'll switch from red apples to green apples and the CPI will show an increase in prices that doesn't reflect what people are really consuming. Also, how do you accurately measure the price changes in a field where the quality of the goods are constantly increasing but the price stays about the same like technology and medicine.
The another way to measure inflation is the GDP deflator or the change in GDP (basically the total cost of everything consumed in the economy in a year) from a base year to the current year. In the apple case the GDP deflator will show that you stopped consuming the expensive red apples for the less expensive green apples. But GDP also includes things not directly consumed by people like government purchases (think expensive aircraft and tanks). Also GDP does not always count imported goods like foreignmade cars.
The way the government economists have tried to fix these problems is through a combination of these two measurements or a weighted CPI. It has been shown that the CPI overestimates inflation by about 0.8 to 1.6 percentage points a year. (See Shapiro and Wilcox "Measurement in the Consumer Price Index: An Evaluation" 1996.)
I don't know about you but I'd prefer to base our measurements on a system that reflects reality than one that costs us much more in taxes each year. 
George R again
If you think about it logically. Lets say that California is expanding at 4 million people a year (a slope of 4 million) and that Texas is expanding at a rate of 3 million. The US would then be expanding by at least 7 million people a year. 
Nate G
You are correct.
I had first looked at the graphs of unemploment rates and then had in mind population rates, but these graphs are of absolute population. 