The auto industry kicked off 2011 with a good first month. The seven biggest automakers combined U.S. sales increased by 17.7% in January compared to the same month in 2010. All seven saw better year-over-year sales, but all seven also saw weaker sales compared to December, which is traditionally a stronger month for auto sales. As always, however, some of the automakers did better than others.

First, here's the chart showing year-over-year sales change:

auto sales year-over-year 2011-01.png

GM and Chrysler continue to improve, as Hyundai continues to grow briskly. All three saw sales increases exceeding 20%.

Here's how sales changed compared to December:

auto sales month-over-month 2011-01.png

Again, Hyundai looks the best here, as its sales only declined by 17%, while the others all saw at least 20% fewer sales. Honda, Toyota, and Ford all saw particularly large drops. But it's important to note that they also all saw gains compared to a year earlier, which is a better metric for comparison given seasonal differences in sales.

Now, let's turn to market share among this universe of automakers. Here's how it has changed over the past year:

auto sales market share comp 2011-01.png

These are mostly small moves. The largest is with GM, which had 0.9% greater share. The biggest decline is actually in case of Ford, with a 0.7% decline.

Here's the pie chart for market share:

auto sales market share pie 2011-01.png

There are no big surprises here. GM, Ford, and Toyota's dominance are pretty clear, accounting for more than 60% of sales. But Hyundai, Nissan, and Chrysler continue to slowly chip away at the leaders' share.

(Sources: GM, Ford, Toyota, Honda, Chrysler, Nissan, and Hyundai)

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