

It can also be noted that the trend over time for the “unknown” category (which stands for 8 % today) follows the same trend as Linux. I don’t think it’s unreasonable to assume that Linux is over-represented in the “unknown” category, and may actually be closer to 5-7 %.
People ditching their PC because they don’t need it anymore doesn’t explain that the relative share of Mac and Linux has increased for the past 15 years though. Unless for some reason Windows users are more likely to ditch their PC because they don’t need it than Mac or Linux users.