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
199525727
199639344
199748025
199859330
199965693
200092137
200183680
200299822
2003113913
2004119743
2005123557
2006133600
2007136480
2008139678
2009146474
2010159066
2011170401
2012242290
2013274966
2014346533
2015329897
2016410790
2017188553
2018257629
2019282255
2020243726
2021192754
2022240763
2023223375
2024104265