Apple's virtual personal assistant Siri is popular, but not nearly as popular as it was last year, according to a new report.

Between the period of May 2016 and May 2017, Siri lost 7.3 million monthly users, or about 15% of its total U.S. user base, according to new data released on Tuesday by app-measurement company Verto Analytics. Even those that are still using Siri have cooled to the app, and are now using it less often than they had in the past, Verto said in a statement.

Still, it's not all bad news for Apple: Siri is still the most popular virtual assistant in the U.S., topping Amazon's Alexa, Microsoft's Cortana, and various other Android-based assistants. Apple 's Siri has 41.4 million monthly unique users in the U.S. It had 48.7 million unique users in May 2016.

Virtual personal assistants have quickly become critical components in both the mobile and smart home markets. The services allow users to issue voice commands to their respective assistants to create calendar appointments, set timers, and search the Web. The assistants run on everything from smartphones to smart home hubs like Amazon's Echo.

With such a large iPhone user base in the U.S., it's perhaps no surprise Apple's Siri is leading the way. The virtual assistant comes bundled with every Apple device, including the iPhone, iPad, and Macs.

While Apple's Siri usage is on the decline, Amazon's Alexa is soaring. The virtual assistant, which runs on smart home devices like the Amazon Echo, had 800,000 U.S. users in May 2016. At the end of May 2017, its user base had grown to 2.6 million. Additionally, Alexa users are proving to be more "sticky" and using the service far more often now than they did last year.

Most other virtual assistants are also seeing their usage climb, due in large part to the number of Android users growing, according to Verto. The researcher didn't say exactly why Siri's usage has declined.

苹果的虚拟个人助手Siri十分受欢迎。但一份最新报告显示，与去年相比，Siri系统受欢迎的程度有所下降。

Verto Analytics是一家进行手机软件测量的公司，根据该公司周二公布的最新数据，2016年5月至2017年5月期间，Siri流失了730万名用户，约占其美国用户总数的15%。Verto Analytics公司在公开文件中称，甚至连那些正在使用Siri的用户也在慢慢冷落这一软件，使用频率比过去低了许多。

不过，对于苹果来说有一个好消息。那就是Siri仍然是美国最受欢迎的虚拟助手，排名超过了亚马逊的Alexa、微软的Cortana以及其他安卓系统中的虚拟助手。在美国，Siri拥有4140万位独立用户。而在2016年5月这一数字为4870万。

虚拟个人助手已迅速成为智能手机市场和智能家居市场的重要组成部分。用户可以向虚拟助手发出语音指令来创建新的日程安排、设定闹钟或是在互联网上搜索。从智能手机到像亚马逊Echo这样的智能家居系统，都是由虚拟助手来运行所有指令。

在美国，iPhone用户群体十分庞大，所以，苹果Siri正在引领这一行业的发展这一说法并不令人感到惊奇。这款虚拟助手与所有苹果设备都可配套使用，包括iPhone、iPad和mac电脑。

就在苹果Siri的用户数正在减少时，亚马逊Alexa的用户数却在飙升。Alexa这款虚拟助手运行于亚马逊Echo这类智能家居系统中。2016年5月，它在美国有80万用户，2017年5月底这个数字已经增长到260万。此外，Alexa的用户十分依赖这一服务，且使用次数比去年更为频繁。

Verto Analytics公司称，其它大多数虚拟助手的使用量也在上升，这在很大程度上是由于安卓用户人数在不断增长。但研究人员并没有给出Siri使用率下降的确切原因。（财富中文网）  

译者：Amelia Huang