Hmm, seeing that Minnesota is projected to lose an EV in 2010, when does it gain one back?
Different population data.
The map for 2020 is based on census projections, in particular an interim projection made in 2004 based on 2000 data. It assumes that trends in death rates, fertility rates, migration rates, etc. will continue indefinitely into the future. So for example, they will take the 2000 population of a state and estimate based on the age distribution of females and the age-based fertility rate how many babies will be born. Similarly it estimates the number of deaths per age, and so on for migration, both interstate and international.
In 2000, Minnesota was entitled to 7.62 representatives. The projection data showed Minnesota growing at almost the same rate as the country did over the next 30 years and staying around 7.62 representatives.
The apportionment estimate for 2010 was based on census estimates (the latest is for July 2006), with the annual growth rate for 2000 to 2006, projected forward to 2010.
The 2005 estimated population for Minnesota was 0.9% less than the 2005 projected population for Minnesota. Put in other terms, the projection had Minnesota growing a 0.51% annually, while the estimate has it growing 0.42% annually. The difference over 5 years is 48,000 people.
Meanwhile the 2005 estimated population for the USA was 0.3% greater than the 2005 projected population. This produces an additional decrease in the relative share of the population for Minnesota. If trends based on the estimates continue, Minnesota will be entitled to around 7.44 representatives in 2010. 7.44/7.62 is 97%, so the relative share decline is small. But since Minnesota is crossing a rounding threshold it may lose the 8th seat.
