Complex sentence: ESRI products (particularly ArcGIS Desktop) have one-third of the global market share, in 2002 ESRI had approximately a 36 percent share of the GIS software market worldwide, more than any other vendor.
Split into simpler sentences: ESRI products (particularly ArcGIS Desktop) have one-third of the global market share. In 2002 ESRI had approximately a 36 percent share of the GIS software market worldwide, more than any other vendor.