It did a lot, mostly because there weren't better games at that time. Back in 2002, it was Yellow, then Gold, Silver and Crystal (2002 or 2003), Sapphire (2007) then Black and White (2011), then Sapphire again (2013) and then XY (2015) and Heart Gold and Soul Silver in recent years. What's funny is that you can see the gap in mid-2000, since there was literally no marketing for Pokémon in my country and games were barely available. Like I only found out about Gen IV at the end of its era.