Backblaze Hard Drive Stats for 2017
Backblaze recently published their yearly stats for hard drive failures for 2017. It covers the latest rate of replacement of spinning drives in the last quarter of 2017, plus their overall failure stats since 2013.
Besides the fact that most drives fail, it's interesting to see their praise for Toshiba and HGST/Hitachi, where certain modules did not fail at all. Although, they readily admit for some the sampling size is low, "The HGST/Hitachi 4 TB models delivered sub 1.0% failure rates for each of the three years", while some Seagate and WD modules have a failure rate of more than 3%.
For more stats from Backblaze see here. Also note their older article and stats on SMART data metrics used predict HDD failure.