CoStar’s building-level, same-store average rent series allows for analysis by building quality across all office markets and submarkets. Comparing the 3 Star (or Grade B) average rent series to the 4 & 5 Star (or Grade A) average rent series in the Bix Six markets reveals that higher quality, 4 & 5 Star space in the Leeds, Manchester and Birmingham markets commands a rent premium of more than 60% over secondary, 3 Star space.