Microsoft vice president of marketing Tami Reller today said that the firm has now sold over 200 million licenses to the beleaguered Windows 8. This confirms that Windows 8 is selling at a much slower rate than its predecessor.

The figure was revealed rather subtly during a Reller appearance at the Goldman Sachs Technology & Internet Conference and was first reported by Mary Jo Foley. Microsoft confirmed the sales figure.

I've reported previously that Windows 8 has sold much slower than Microsoft had anticipated, and the firm has been updating the software with free updates to appease disgruntled customers. But with this figure, we can now determine just how poorly Windows 8 has sold. And while 200 million is obviously a big number, it's not pretty.

200 million licenses in 16 months equates to about 12.5 million licenses per month. The last time Microsoft revealed a sales figure for Windows 8 was in May 2013: At that time, it said it had sold over 100 million licenses, a pace of about 16.6 million units per month. So sales have in fact been slowing over time.

But Windows 7 consistently sold 20 million licenses per month over its three years in the market. And the firm was able to sell 240 million licenses to Windows 7 in just one year, a pace of ... wait for it ... 20 million units per month. (Windows 7 sales were curiously always very consistent.) So Windows 8 is falling far short of its predecessor.

While critics of Microsoft and Windows will point out that Windows 8 license sales don't equate to sales to end users and are instead "sell in" numbers that include sales to PC makers as well as consumer upgrades, it's not all bad news. This figure doesn't include volume licenses to businesses, which is Microsoft's biggest customer base.