What percent of WordPress installs are on Linux vs. Windows servers?

It seems the bulk of WP servers running on hosting providers are using Linux servers. Does anyone know the actual numbers?

I wrote a gallery plugin that makes use of the parent operating system. This often requires duplicating effort to add the same feature for both Linux and Windows. If the split was 60/40, I would probably put more effort into supporting each platform, vs. if the split were 90/10.

Thanks,
Mark
https://markpreynolds.com/