I have a real life problem for you. I need the appreciation rate of a neighborhood to help decide how much a house I am considering may be worth.

I converted a list of house sales price and the size to get the square footage of the houses.

Now I have the following price/sq foot numbers and years the houses sold.

How would I get an average appreciation for the neighborhood? We can not look at just the first and last points because these are different houses. One may have sold for more and one for less. So I am looking for the correlation and using that to get average interest rate.

1995 $38.69
1997 $34.47
1998 $38.03
1999 $42
2001 $37.06
2001 $36.67
2004 $28.56
2005 .79

2005 $58.57


I think the houses appreciated between 2 and 3 percent a year but how do I get an exact average?
I tried to do a correlation but ended up confused as to how I would back out the appreciation rate.

Thanks in advance!