Backblaze on December 31, 2014 had 41 213 hard drives in operation, which is slightly different from the end of 2013 - 27,134. Most of the new drives in 2014 are 4TB drives, and some of them are new 6TB drives. According to the results of 2014, they published statistics on failures. Please in the comments of each other do not minsovat for IMHO.
The result is clearly displayed in two diagrams and one table.
Table and more statistics can be seen in the
original publication .
PS My apologies for typographical errors and short text - I am writing from the Live CD due to the demise of the hard drive produced by the leader of the hit parade.