Only Apple had a good holiday quarter for PC sales
Gartner noted that every major manufacturer - which includes HP, Lenovo, Dell, Asus, Apple, and Acer - bar Apple saw a sales decline.
Acer saw the biggest decline, shipping six million PCs over the three month period, an 11% drop from the same quarter in 2014. HP, which recently broke into two new companies, saw the second biggest decline, with sales falling over 8% year-over-year to 15 million units.
The data does not include tablets, according to Gartner.
Apple saw sales increase to 5.5 million units, up by 3% year-over-year. The Mac is one of Apple's most successful product lines when compared to the broader industry: Sales have continued to increase, despite an overall decline in PC sales every year.
Lenovo is still the biggest PC maker by volume, shipping a total of 16 million PCs, although this figure is down 4.2% over 2014. HP comes in next, with 15 million PC sales.
For many customers, tablets and 2-in-1 devices - a combined laptop and tablet - have overtaken PCs as the go-to device for tasks that would traditionally have been carried out on a computer.
Microsoft has invested heavily in 2-in-1s, remaking Windows to work on a touchscreen and building the Surface Book and Pro models.
In an interview with The Telegraph, Apple CEO Tim Cook questioned why anyone would want a PC. "I think if you're looking at a PC, why would you buy a PC anymore? No really, why would you buy one?" he said. According to Cook, the iPad Pro - a larger, more powerful iPad - is enough for most people.