Over the past year we’ve been releasing hard drive reliability statistics based on the drives we use to store customer data for our online backup business. As of the end of Q1 2015 we had 44,252 hard drives spinning in our datacenter. If we subtract boot drives and drive models with less than 45 drives from that total, we get 42,749 hard drives remaining spread across 21 drive models. Below are the hard drive reliability statistics for these drives for Q1 2015. —The Ultimate Hard Drive Test: What Hard Drive is Best?