1. Ground-Based Global Navigation Satellite System Observation Summary Data (30-second sampling, daily files) from NASA CDDIS
  2. temporal
YearFile Count
199214838
199324076
199420289
199525734
199639707
199748415
199859998
199966591
200092745
200183971
2002100116
2003114211
2004120046
2005123858
2006133900
2007136780
2008139978
2009146772
2010159429
2011170763
2012242650
2013275330
2014346887
2015330256
2016411151
2017188910
2018258315
2019286672
2020248335
2021195637
2022244852
2023228951
2024211027
2025147138