Not Orlando, not Trump victory: Las Vegas shooting was Twitter’s saddest day ever

The previous record low was 5.84 on the day of another mass shooting in Orlando, Florida that killed at least 49 people and injured more than 50 last year.

The mass shooting in Las Vegas, in which at least 59 people were killed and more than 500 injured, was the saddest day ever recorded on Twitter, according to Hedonometer, a tool that measures sentiment on social media platforms.

People attend a candlelight vigil for victims of the Route 91 music festival mass shooting next to the Mandalay Bay Resort and Casino in Las Vegas, Nevada. (Reuters Photo)

The barometer, which measures the happiness of millions of Twitter users based on their posts, showed an average happiness level of 5.77 on Monday when the deadliest mass shooting in modern US history occurred at a country music festival in Las Vegas.

The previous record low was 5.84 on the day of another mass shooting in Orlando, Florida that killed at least 49 people and injured more than 50 last year.

A woman lights a candle at a makeshift memorial near the Mandalay Hotel on the Las Vegas Strip, in Las Vegas, Nevada.

A message of condolences for the victims of Sunday night's mass shooting is displayed outside the Mandalay Bay Resort and Casino in Las Vegas, Nevada.

The third saddest recorded day on Twitter was November 9, 2016, the day after Donald Trump was elected president of the United States, according to Hedonometer. The barometer on that day was 5.87.

Hedonometer was invented by Peter Dodds and Chris Danforth, a mathematician and computer scientist at the University of Vermont’s Advanced Computing Center. It gathers sentences that start with “I feel” or “I am feeling” and generates a happiness score for the text. Each sentence is then given a happiness score from 1 to 9.