• Company says issue was related to an internal code change
  • The stock has declined more than 28 percent this year

Twitter Inc. shares slumped to a new all-time low after the company’s website suffered disruptions, shutting out millions of users and underscoring concerns about the company’s efforts to boost its audience and sales.

Services including search and the news stream were unavailable for more than five hours after the company’s software engineers made changes to the service that lets people post and share 140-character status updates. The stock fell 7 percent to $16.69 at the close on Tuesday, well below the price of $26 at its November 2013 initial public offering.

Users of Twitter’s mobile applications and website experienced a string of outages since Friday, as the company tweaks its features and services to improve the user experience and address a slowdown in growth. The glitches come at an inconvenient time for the company, which has to prove its value to any new users and keep existing ones from leaving in frustration.

“The issue was related to an internal code change,” Twitter said on its website. “We reverted the change, which fixed the issue.”

Services including search and the news stream were disrupted, according to the company’s performance status website. The top trending hashtag for about the past two hours was #twitterdown. Prior to the latest round of issues, Twitter’s last outage was about two months ago.

Twitter’s stock has tumbled more than 28 percent in January, following a 35 percent decline in 2015. Of the 43 analysts covering the stock, 40 percent recommend buying it.