The tables give total staff in FTEs and break the total into various categories. The different organizational structures of the centers make comparison across these categories problematical, and caution should be exercised in drawing conclusions based on this breakdown. EPO is an exception in that it is an activity that can be reliably identified and broken out, and the numbers shown for EPO are a reasonable indicator of effort.

The number of fellows supported in FY 2005 by centers that have fellowship programs is shown. The fellowships can be taken up at any participating institution, so the numbers do not indicate how many fellows are at the science center itself, nor do they indicate the number of postdoctoral fellows who may be present at the science center.

As an indicator of the size of the community served by a center, Table A.1 lists the number of individuals, counted once, who were PIs or co-investigators on an approved observing or archive proposal in 2004. This number includes foreign investigators.

Table A.1 shows the number of grants to users for data analysis in 2004. Because only PI grants are shown, not grants to co-investigators as well, the numbers here reflect the number of observing programs rather than the total number of people supported, which is greater.

Table A.1 gives the number of mission-related publications in refereed journals for the year 2004. Obviously, this number is influenced by how the center defines “mission related.” Caution should be exercised in drawing conclusions based on this metric.

The total size, annual ingress, and number of data requests (downloads) for 2005 are given. The number of downloads shown for CXC has been reduced by ~20 percent, the total requested by a single science data center in China, to more accurately reflect the usage by the broad astronomical community.