Is it possible to get CityData for different years? Or get a year of origin of data in CityData?
3 Answers
There is new functionality in 10.3 called EntityInstance.
nyc1890 =
EntityInstance[
Entity["City", {"NewYork", "NewYork", "UnitedStates"}],
"Date" -> 1890];
nyc1890["Population"]
(*Quantity[1515301, "People"]*)
nyc2015 =
EntityInstance[
Entity["City", {"NewYork", "NewYork", "UnitedStates"}],
"Date" -> 2015];
nyc2015["Population"]
(*Quantity[8491079, "People"]*)
Lets Graph the population trend.
ListPlot[{#,
EntityInstance[
Entity["City", {"NewYork", "NewYork", "UnitedStates"}],
"Date" -> #]["Population"]} & /@ Range[1890, 2015, 5],
Joined -> True, PlotLabel -> "NYC Population",
PlotTheme -> "Detailed", FrameLabel -> {"Year", "Population"}]
You can get the year of origin with f.e.
CityData["Seattle", "Population", "Date"]
2004
Unlike f.e. TemperatureData
you can't get CityData
for different years.
However, you can make a WolframAlpha
query which will give you some historical data.
For example
data=
WolframAlpha["Seattle", {{"Population:CityData", 3}, "ComputableData"},
PodStates -> {"Population:CityData__Show history"}]
DateListPlot @ data
CityData["London", "Population", "Date"]
(* 2004 *)
CityData["London", "Population"]
(* Quantity[8173941, "People"] *)
WolframAlpha
query via Mathematica indicates that the city population for London is a 2011 estimate (no base for estimate given) -- but agrees roughly (8.174 million people) with the (2004?) value returned by CityData
; whereas, the London metro area population is a 2007 estimate (no base for estimate given). I would conclude that the CityData
is neither current nor accurate.
WolframAlpha["city population of London"]