wells fargo housing economist richard dekaser says housing currently comprises only about 2.5% of u.soss domestic product, but as it improves, he thinks it will have a dramatic influence on the economy. >> people go out and they buy new homes, and they purchase various kinds of merchandise furniture and appliances, for instance. that has a ripple effect which makes its way into the broader economy, and ultimately this has a powerful effect on overall macro-economic growth. >> reporter: that's already beginning to happen for home improvement chains like home depot and lowes. the stocks of both companies have been tracking improvement in the housing market for several months. >> what we are seeing is that, with the improvement in the unemployment rates, they are benefiting from increased traffic and an increase in repair and remodeling activities. so i think that a lot of that has to do with the trends that we are seeing in the housing market today. >> reporter: tighter inventories of both new and existing homes is adding another dynamic to the u.s. economy. last week, the national asso