Here is a chart of as many Microsoft Published console games as I could find.  Data only goes back to 2002, so I couldn't find the first Halo NPD.

This only goes back to around 2002 because data before then is hard to find.  Also I don't have any of the sports games, or kinnect/casual games, but I will add a seperate chart for them later.

Here they are in order from largest to smallest:

As you can see, Halo, and to a lesser extent Gears are massive.  Compare that to the sony chart, where Sony has only published 1 game in the last 15 years that got >1,000,000 sales in the first NPD.

Which Sony game got more than 1 million in the first NPD?

pretty sure most GT games did. That said Sony has never had an IP as big as Halo in the US, so not suprising.

I checked the thread in the OPs sig, and according to that, only GoW 3 did. TLOU came pretty darn close though.

I find it interesting that Halo 4 sold less opening month that Halo 3 despite the massive increase in userbase. Not a good sign for Halo 5 on the small XB1 userbase. It also looks like the same 3.3 million Halo fans keep going out and getting it month one. (I know its not exactly the same people, but the fact they are all with 5% of each other is a bit odd).

Gears however seemed to take advantage of the growing userbase with each release launching better than the last one.

That top 15 though.

Wow, only Halo, Gears, Fable and Forza sell.

I think that Halo 5 will sell more than Halo 4 and maybe even edge out Halo 2.

Great work!!