Holdings
1.1992,1-8; 2.1993,1u.2u.4-12; 3.1994,1-12; 4.1995,1-12; 5.1996,1-10; 6.1997,1-12; 7.1998,1u.3-12; 8.1999,1u.2u.4-7; 9.2000,3-6u.8u.10-13; 10.2001,1-7u.9-11u.13u.15u.16; 11.2002,2-12; 12.2003,1-11u.13; 13.2004,1u.3-12; 14.2005,1-3u.5u.7u.12u.15u.17; 15.2006,5u.7u.9u.11u.12u.14u.16u.18u.20u.21; 16.2007,2u.4u.6u.8u.11u.12u.14u.15u.17u.19u.21; 17.2008,2u.4u.6u.9u.11u.13u.15u.19u.22u.24; 18.2009,1u.3u.5u.7u.10u.12u.14u.15u.20u.22u.23; 19.2010,11u.13-15u.17u.19-22; 20.2011,1u.2