restart;
data:={ [1970,273288], [1980,463087], [1990, 741459], [2000, 1375765], [2010,1951269]};

with(plots):
# Warning, the name changecoords has been redefined
P1:=plot(data,style=point,symbolsize=30,thickness=2):
# Polynomial model from book with 4 paramters
p:=t->44560*t^3-89394*t^2+234633*t+273288;

P2:=plot(p((t-1970)/10),t=1970..2010):
display(P1,P2);

# Logistic model based on exponential growth and carrying capacity
f:=x->L/(1+exp(-k*(x-x0)));

# The 3 parameters obtained by fitting the data
L    := 3.00001e+06;
k    := 0.0790773;
x0   := 2002.41;



P3:=plot(f(t),t=1970..2010):
display(P1,P3);