Early indications suggest sales of Activision’s latest Call of Duty game may be significantly lower than anticipated.

In a recent note to clients, Cowen analyst Doug Creutz said physical sales of Call of Duty: Infinite Warfare came in roughly 17 percent shy of their expectations. A second source confirmed the results with CNBC, noting that year-over-year sales for the month of November were down 51 percent.

Data from both sources came from market research firm The NPD Group (NPD) which shared its findings with investors ahead of a public release that’ll take place sometime this week.

The findings also jibe with what we heard out of the UK regarding first week sales of Infinite Warfare compared to last year’s Black Ops III.

There are, however, a handful of caveats worth pointing out such as the fact that NPD’s data only covers physical retail sales.

As you’ve no doubt noticed over the past few years, gamers are increasingly turning to digital downloads. Virtually everyone was expecting retail sales to slide although such a big drop like this wasn’t anticipated. On the flip side, digital sales are forecasted to increase and will offset some of retail’s downturn but by how much remains to be seen.

Activision this year also bundled a remastered version of Call of Duty: Modern Warfare with special editions of Infinite Warfare, the cheapest of which starts at $80. What that means is that while overall sales may be down, the additional money Activision rakes in from those buying a more expensive special edition will help pad the financials a bit. Upcoming DLC will also bring in more money, just as it does every year.

Furthermore, Infinite Warfare is the first CoD game (in many years) that wasn’t released on aging PlayStation 3 and Xbox 360 consoles. Last year’s Black Ops III was available for these older systems albeit with some major shortcomings.

One must not overlook the fact that many gamers were unhappy with Activision’s move to further push the gameplay into the future, especially as rival EA made the decision to set Battlefield I in the WWI era. Fans made their voice heard loud and clear on YouTube as the Infinite Warfare reveal trailer has garnered nearly four million dislikes compared to just 560,606 thumbs-up votes.

It’s also easy to overlook the fact that this is a new sub-series for Call of Duty rather than an established series like Black Ops or Modern Warfare.

Activision no doubt has a lot stacked against it with Infinite Warfare but until we see digital sales figures, it’s hard to know exactly how much the franchise has slid.