Since the first stations officially commenced HD Radio transmissions in 2002, the number of stations implementing the technology has steadily increased. At the end of 2006, 1,133 stations were transmitting an HD Radio signal. The number of stations multicasting has also increased so that nearly half of all HD Radio stations provide at least one additional program stream.

Based on the trend shown here, it's likely that there will be about 1,600 radio stations transmitting an HD Radio signal by the end of 2007.

Because multicasting is relatively new, it's hard to predict an exact trend yet, but while the percentage increase in the number of stations adding HD Radio equipment will likely drop, those stations already transmitting an HD Radio signal but not yet multicasting will likely see a steady increase. This is because most HD Radio equipment already installed has multicast capability, but stations may not have had a secondary program source available.

Why the potential slowdown in the HD Radio roll-out? The larger groups have already made their commitments by converting the easier stations first. The remaining stations within the large groups appear to be the more challenging installations.

Data source: lbiquity Digital