Table 1: Input catalogues. The last column shows number of sources in the catalogue and the number of reference sources used to tie the orientation of the catalogue to the ICRF.

Center	Software	Time span	Number of
		month/year	delays	sources
AUS	OCCAM	11/1979 - 12/2004	3208197	737(207)
BKG	Calc/Solve	01/1980 - 01/2005	4031453	748(212)
DGFI	OCCAM	01/1980 - 01/2005	3650771	686(199)
GSFC	Calc/Solve	08/1979 - 01/2005	4574189	954(212)
JPL	MODEST	10/1978 - 01/2005	3575847	734(2)
MAO	SteelBreeze	10/1980 - 01/2005	3773765	685(25)
SHAO	Calc/Solve	04/1980 - 01/2005	4431503	813(212)
USNO	Calc/Solve	09/1979 - 01/2005	4252684	943(207)