Split-rate in PA increased growth in number of housing units by 2-5% relative to control groups.

"Our central estimates, based on linear fixed effects regression, are that a split rate tax increases the growth in the total number of rooms by about 3-6 percentage points per decade (in the first decade or two after adoption) relative to control areas. There is a small and statistically insignificant effect on the average number of rooms per housing unit, and a 2-5 percentage point increase in the number of housing units. The point estimates are slightly larger but statistically insignificant using an alternative non-parametric matching procedure."