Price vs Rent Ratio in bay area

[Sid N.]

I am trying to map historical price v/s yearly rent ratio . One of the tools I want to use for my analysis .This ratio is location specific and texas would have  totally different ratio then bay area and even in bay area there would be discrepancy across hot areas v/s normal .In Fremont,CA  during the peak of 2005  Price/Yearly rent was at 27(approx) .. Now this ratio is around 22 . I believe rentals really mark the affordability and home price affordability + investing euphoria . If Euphoria was not there we would be living in a perfect world :-) . hence this ratio to me is important . If jobs increase rental prices will increase hence keeping in balance the ratio , however due to invester sentiment the ratio will still decrease further . One of the factors would be to get out of the real estate market when this ratio is around 25 in Fremont . Any thoughts ?