from the "Can you explain the Net Market Share methodology for collecting data?" part of NetMarketShares FAQ[0]: "[...]43% are commerce sites [...]"

Could it just be that christmas shopping skews these statistics? Then again, statistics for the previous years don't seem to support this theory.

All in all this doesn't seem like information I would want to base any claims on.

[0] -> https://www.netmarketshare.com/faq.aspx#methodology