According to MEMS Journal's research, the market for hearing aids is approximately $14 billion in the US alone, with an estimated 9.5 million individuals wearing hearing aids today. The cost of high quality hearing aids remains high at $2,000 to $3,500 per unit. Inexpensive hearing aids can cost as little as $300 to $400, but their performance is quite limited. The total hearing loss population is approximately 38 million in the US; in other words, most people who have hearing loss do not wear a hearing aid. The hearing health industry started to adopt MEMS microphones in 2010, and Knowles reported that it surpassed the one million mark for distribution in November 2013. The company says that it has now reached the second million unit milestone, four times faster than the fist million due to increased customer demand. With the approximate cost of $10 to $20 per device, the MEMS microphone component represents a very small fraction of the overall hearing aid unit cost. Nevertheless, the market is an attractive opportunity for MEMS device makers.