Super Sentai and Kamen Rider Toy Sales

1991 - Jetman - 11.3 Billion Yen

1992 - Zyuranger - 13.2 Billion Yen
1993 - Dairanger - 7.8 Billion Yen
1994 - Kakuranger - 8.4 Billion Yen
1995 - Ohranger - 15.9 Billion Yen
1996 - Carranger - 11.8 Billion Yen
1997 - Megaranger - 7.3 Billion Yen
1998 - Gingaman - 9.3 Billion Yen
1999 - GoGoV - 9 Bilion yen

In the 90's, it seems that Ohranger sold the most, surprisingly since supposedly Ohranger was the worst season. Megaranger was the least selling at 7.3 Billion.
2000 - Timeranger - 4 Billion Yen
2001 - Gaoranger - 14.5 Billion yen
2002 - Hurricanger - 10.3 Billion Yen
2003 - Abaranger - 13 Billion Yen - 75 + 55
2004 - Dekaranger - 11.6 Billion Yen - 63+53
2005 - Magiranger - 10.8 Billion Yen - 63+45
2006 - Boukenger - 10.1 Billion Yen - 54+47
2007 - Gekiranger - 7.7 Billion Yen - 40+37
2008 - Go-Onger - 12 Billion Yen - 62+58
2009 - Shinkenger - 12 Billion Yen
2010 - Goseiger - 9.3 Billion Yen
Gaoranger seems to be the best selling of the 00 decade, not as high selling as Ohranger. Gekiranger was the least selling of that decade at 7.7 billion, but not as low as Megaranger. Timeranger made less.

Source is Gekiranger Japanese Wikipedia

As for Kamen Rider...
2000 - Timeranger - 4 Billion Yen
2000 - Kamen Rider Kuuga - 11.8 Billion Yen
2001 - Kamen Rider Agito - 9.4 Billion Yen
2002 - Kamen Rider Ryuki - 13.9 Billion Yen
2003 - Kamen Rider 555 - 12 Billion Yen
2004 - Kamen Rider Blade - 7.9 Billion Yen
2005 - Kamen Rider Hibiki - 6.5 Billion Yen
2006 - Kamen Rider Kabuto - 7.1 Billion Yen
2007 - Kamen Rider Den-O - 11.5 Billion Yen
2008 - Kamen Rider Kiva - 8.5 Billion Yen

I do not know about Decade, Double or OOO. Ryuki made the most money and the least would be Hibiki, not surprisingly.

Sales of Super Sentai and Kamen Rider from Jetman to Goseiger, Kuuga to Kiva. You can see it went up with Ohranger and went down with Timeranger and jetted back up with Gaoranger. As for Kamen Rider, it was pretty high with Ryuki and lowered through the years until Den-O. I made this chart.

Super Sentai Sales vs. Kamen Rider Sales
2000
2000 - Timeranger - 4 Billion Yen
2000 - Kamen Rider Kuuga - 11.8 Billion Yen
It seems Kuuga made more that year.

2001
2001 - Gaoranger - 14.5 Billion yen
2001 - Kamen Rider Agito - 9.4 Billion Yen
It seems Gaoranger made more that year.

2002
2002 - Hurricanger - 10.3 Billion Yen
2002 - Kamen Rider Ryuki - 13.9 Billion Yen
Ryuki seems to have won that year, Ryuki made more than Agito, but Hurricanger made less than Gaoranger. In fact, Ryuki earned less than Gaoranger.

2003
2003 - Abaranger - 13 Billion Yen
2003 - Kamen Rider 555 - 12 Billion Yen
Abaranger did better than 555, Abaranger did better than Hurricanger but not as much as Gaoranger. 555 made less than Ryuki.

2004
2004 - Dekaranger - 11.6 Billion Yen
2004 - Kamen Rider Blade - 7.9 Billion Yen
Dekaranger did less than Abaranger but made more than Blade that year. Blade made less than 555.

2005
2005 - Magiranger - 10.8 Billion Yen
2005 - Kamen Rider Hibiki - 6.5 Billion Yen
Magiranger made less than Dekaranger and Hibiki made less than Blade. That year, Magiranger made more than Hibiki.

2006
2006 - Boukenger - 10.1 Billion Yen
2006 - Kamen Rider Kabuto - 7.1 Billion Yen
Boukenger made less than Magiranger, Kabuto made more than Hibiki. That year, Boukenger made more than Kabuto.

2007
2007 - Gekiranger - 7.7 Billion Yen
2007 - Kamen Rider Den-O - 11.5 Billion Yen
Gekiranger made less than Boukenger, but more than Kabuto. Den-O made more than Gekiranger and more than Boukenger did.

2008
2008 - Go-Onger - 12 Billion Yen
2008 - Kamen Rider Kiva - 8.5 Billion Yen
Go-Onger made more than Kiva, even more than Den-O. Kiva made less than Den-O.

So in that decade, the only Kamen Riders series that succeeded the Super Sentai were Den-O and Ryuki.

I made this chart, comparing the Kamen Rider and Super Sentai from 2000 to 2008, as I don't have the numbers for Decade, Double or OOO.